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  • 101.
    Li, Qiang
    et al.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik, Fotonik.
    Song, Yi
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik, Kvantelektronik och -optik, QEO.
    Zhou, Gan
    Su, Yikai
    Qiu, Min
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik, Fotonik.
    Asymmetric plasmonic-dielectric coupler with short coupling length, high extinction ratio, and low insertion loss2010Ingår i: Optics Letters, ISSN 0146-9592, E-ISSN 1539-4794, Vol. 35, nr 19, s. 3153-3155Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Asymmetric directional coupling between a hybrid plasmonic waveguide with subwavelength field confinement and a conventional dielectric waveguide is investigated. The proposed hybrid coupler features short coupling length, high coupling efficiency, high extinction ratio, and low insertion loss; it can also be integrated into a silicon-based platform. This coupler can be potentially adopted for signal routing between plasmonic waveguides and dielectric waveguides in photonic integrated circuits. Furthermore, it can be exploited to efficiently excite hybrid plasmonic modes with conventional dielectric modes.

  • 102.
    Li, Qiang
    et al.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik, Fotonik.
    Wang, Shanshan
    Chen, Yiting
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik, Fotonik.
    Yan, Min
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik, Fotonik.
    Tong, Limin
    Qiu, Min
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik, Fotonik.
    Experimental Demonstration of Plasmon Propagation, Coupling, and Splitting in Silver Nanowire at 1550-nm Wavelength2011Ingår i: IEEE Journal of Selected Topics in Quantum Electronics, ISSN 1077-260X, E-ISSN 1558-4542, Vol. 17, nr 4, s. 1107-1111Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We experimentally demonstrate silver-nanowire-based plasmonic devices including the nanowaveguide, the nanocoupler, and the nanosplitter at optical communication wavelength of 1550 nm. The plasmon propagation loss in a 300-nm diameter silver nanowire is measured to be 0.3 dB/mu m and the effective propagation length is 14.5 mu m. This loss is comparatively lower than that at 980 nm. Two types of plasmonic functional devices based on the coupling between two silver nanowires, nanocouplers, and nanosplitters, are realized. For the nanocoupler, the experimental results show that the plasmonic modes can be efficiently coupled between two closely positioned nanowires. While for the nanosplitter, the plasmonic mode is split with a power ratio of 2.6:1. These demonstrations experimentally prove the feasibility of extending the operating wavelength of silver-nanowire-based plasmonic devices to current optical communication wavelength with a lower loss, which are thus important steps for potentially utilizing low-loss nanowire-based plasmonic components for photonic integrated circuits.

  • 103.
    Li, Qiang
    et al.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik, Fotonik.
    Wang, Shanshan
    Chen, Yiting
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik, Fotonik.
    Yan, Min
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik, Fotonik.
    Tong, Limin
    Qiu, Min
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik, Fotonik.
    Silver nanowire based plasmon propagation, coupling and splitting at 1.55 mu m wavelength2011Ingår i: Proceedings of SPIE, the International Society for Optical Engineering, ISSN 0277-786X, E-ISSN 1996-756X, Vol. 7986Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We experimentally demonstrate silver nanowire based plasmonic devices at optical communication wavelength 1.55 mu m. The plasmon propagation loss in a 300 nm diameter silver nanowire is measured to be 0.3 dB/mu m. Two types of plasmonic functional devices based on the coupling between two silver nanowires, nano-couplers and nano-splitters, are realized.

  • 104.
    Li, Qiang
    et al.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik, Fotonik.
    Wang, Tao
    Su, Yikai
    Yan, Min
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik, Fotonik.
    Qiu, Min
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik, Fotonik.
    Coupled mode theory analysis of mode-splitting in coupled cavity system2010Ingår i: Optics Express, ISSN 1094-4087, E-ISSN 1094-4087, Vol. 18, nr 8, s. 8367-8382Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We analyze transmission characteristics of two coupled identical cavities, of either standing-wave (SW) or traveling-wave (TW) type, based on temporal coupled mode theory. Mode splitting is observed for both directly (cavity-cavity) and indirectly (cavity-waveguide-cavity) coupled cavity systems. The effects of direct and indirect couplings, if coexisting in one system, can offset each other such that no mode splitting occurs and the original single-cavity resonant frequency is retained. By tuning the configuration of the coupled cavity system, one can obtain different characteristics in transmission spectra, including splitting in transmission, zero transmission, Fano-type transmission, electromagnetically-induced-transparency (EIT)-like transmission, and electromagnetically-induced-absorption (EIA)-like transmission. It is also interesting to notice that a side-coupled SW cavity system performs similarly to an under-coupled TW cavity. The results are useful for the design of cavity-based devices for integration in nanophotonics.

  • 105.
    Liu, Hairong
    et al.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik, Fotonik.
    Yan, Min
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik, Fotonik.
    Qiu, Min
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik, Fotonik.
    Liu, Deming
    Yu, Xia
    Zhang, Ying
    Theoretical investigation on guiding IR light in hollow-core metallic fiber with corrugated inner surface2010Ingår i: Optics Express, ISSN 1094-4087, E-ISSN 1094-4087, Vol. 18, nr 21, s. 21959-21964Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Hollow metallic fibers (HMFs) are in general lossy primarily owing to the fact that the guided transverse-magnetic (TM) light sustains a relatively high propagation loss. In this paper, we propose a type of practical hollow-core metallic fiber (HMF) with longitudinally corrugated inner surface for transmitting infrared (IR) light. Simulation results show that the loss of the fundamental TM mode can be easily reduced by 50 similar to 100 times compared to a HMF without surface corrugation. In contrast to the traditional HMF with a dielectric coating, it is shown that the loss of the fundamental TM mode in the proposed HMF is relatively insensitive to the corrugation layer thickness or equivalently the operating frequency.

  • 106.
    Lourdudoss, Sebastian
    et al.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Mikroelektronik och Informationsteknik, IMIT. KTH, Skolan för informations- och kommunikationsteknik (ICT), Mikroelektronik och tillämpad fysik, MAP. KTH, Skolan för informations- och kommunikationsteknik (ICT), Materialfysik, Halvledarmaterial, HMA.
    Kjebon, Olle
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Mikroelektronik och Informationsteknik, IMIT. KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik, Fotonik.
    Schatz, Richard
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Mikroelektronik och tillämpad fysik, MAP. KTH, Skolan för informations- och kommunikationsteknik (ICT), Mikroelektronik och Informationsteknik, IMIT. KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik, Fotonik.
    Nilsson, Stefan
    Stålnacke, Björn
    Fabrication and analysis of directly modulated 1.55 µm semiconductor lasers of bandwidth up to 30 GHz1997Ingår i: 4th Annual meeting of European Research Network of Excellence on the Physics and Technology of Mesoscopic Systems (Phantoms), March 1997, Aachen, Germany, paper D2.11., 1997Konferensbidrag (Refereegranskat)
  • 107. MacHuca, C. M.
    et al.
    Chen, Jiajia
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik, Fotonik.
    Wosinska, Lena
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik, Fotonik.
    Mahloo, Mozhgan
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik, Fotonik.
    Grobe, K.
    Fiber access networks: Reliability and power consumption analysis2011Ingår i: ONDM 2011 - 15th Conference on Optical Network Design and Modeling, Bologna, 2011, s. 5753402-Konferensbidrag (Refereegranskat)
    Abstract [en]

    Optical access networks are being widely deployed due to their high capacity and scalability. The reliability of these networks is a key issue because of the impact of failures on both the number of interrupted services and significance of the service interruptions for the community. Consequently, the service interruption penalties that a network operator would need to pay are directly related to the network reliability performance. Nowadays, penalties are paid to business customers when the service interruption time is longer than the value of the Service Level Agreement agreed with the operator. However, the number of users requesting penalties increases, which has triggered the need of protection mechanisms in access networks. In this paper, the investments required to offer protection for different planning approaches will be compared for different optical access technologies (TDM, WDM, AON and P2P). The evaluation of the costs associated to each scenario such as infrastructure, equipment, power consumption, failure reparation etc. is presented. The overall cost reduction when investing on infrastructure protection is highlighted.

  • 108. Machuca, Carmen Mas
    et al.
    Chen, Jiajia
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik (Stängd 20120101), Fotonik (Stängd 20120101).
    Wosinska, Lena
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik (Stängd 20120101), Fotonik (Stängd 20120101).
    Cost dependency on protection of optical access networks for dense urban areas2011Ingår i: International Conference on Transparent Optical Networks, Stockholm, 2011Konferensbidrag (Refereegranskat)
    Abstract [en]

    Along with the competition on the telecom market and high reliability requirements of the emerging services operators and service providers are forced to increase connection availability of all users supported by their network. For economical reason most of the investment related to providing protection resources has been so far limited to the core and metro networks. On the other hand, increasing requirement for interrupted access to the network services is moving the focus for protection towards the end user. However, the cost to offer protection in access networks is a limiting factor. In this paper, a protection scenario for passive optical network in dense urban area is proposed. The cost of this protection approach is analysed, and furthermore, the key cost drivers are identified. It is shown that the failure rates of fiber and Optical Network Units (ONUs) and basic salary of technicians are the main cost drivers for the considered dense urban area.

  • 109. Machuca, Carmen Mas
    et al.
    Chen, Jiajia
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik, Fotonik.
    Wosinska, Lena
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik, Fotonik.
    Impact of protection to capital and operational expenditures of optical access networks2011Ingår i: Photonische Netze - 12. ITG-Fachtagung, 2011Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    Reliability is becoming a crucial issue for service providers, operators and users in optical access networks. The increase of network capacity and the importance of reducing service interruption times, force network operators to implement protection mechanisms in optical access networks. However, so far providing backup resources in access networks has been considered too expensive. In order to assess the impact of protection on capital and operational expenditures, the evaluation needs to study the impact to aspects such as the required infrastructure and equipment costs, failure reparation costs, and expected service interruption time. This work deals with the cost and reliability evaluation of time-division-multiplexing (TDM) and wavelength-division-multiplexing (WDM) passive optical networks (PONs). Three strategies to offer protection are evaluated: 1) provide protection in the access network directly from the greenfield, 2) invest initially on an unprotected architecture keeping in mind a future upgrade with protection resources, and 3) roll out an unprotected access network and if needed in the future, invest in deployment of protection resources. The impact of these strategies on the overall cost is studied.

  • 110.
    Mas Machuca, Carmen
    et al.
    Technische Univ. München (Germany).
    Mahloo, Mozhgan
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS.
    Chen, Jiajia
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik (Stängd 20120101), Fotonik (Stängd 20120101).
    Wosinska, Lena
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik (Stängd 20120101), Fotonik (Stängd 20120101).
    Protection cost evaluation of two WDM-based next generation optical access networks2011Ingår i: Proceedings of SPIE: The International Society for Optical Engineering, 2011, s. 83100P-Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    In this paper, we investigate the capital and operational expenditures for two next generation optical access (NGOA) networks based on wavelength division multiplexing (WDM) technology in dense urban areas. It is shown that with a proper fiber layout design, minor extra investment for protection of NGOA networks can make a significant saving on failure related operational cost.

  • 111. Matsui, Yasuhiro
    et al.
    Mahgerefteh, Daniel
    Zheng, Xueyan
    Ye, Xiong
    McCallion, Kevin
    Xu, Haitao
    Deutsch, Michael
    Lewen, Robert
    Wesström, Jan-Olof
    Schatz, Richard
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik, Fotonik.
    Rigole, Pierre-Jean
    Widely tuneable modulated grating Y-branch Chirp Managed Laser2009Ingår i: 35th European Conference on Optical Communication, 2009. ECOC ’09, 2009, Vol. 2009-SupplementKonferensbidrag (Refereegranskat)
    Abstract [en]

    We developed a 45 nm tuneable 18 GHz 3-dB bandwidth Modulated-Grating Y-branch laser and demonstrated a error-free 200- km transmission at 10 Gb/s with a drive voltage of 1.5 Vpp using Chirp Managed Laser technology.

  • 112. Mazandu, G. K.
    et al.
    Bagula, A. B.
    Wosinska, Lena
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik, Fotonik.
    Impairment Aware Multi-path Routing in GMPLS-based Networks2008Ingår i: Optical Fiber communication/National Fiber Optic Engineers Conference, 2008. OFC/NFOEC 2008. Conference on, Optical Society of America, 2008, s. 718-723Konferensbidrag (Refereegranskat)
    Abstract [en]

    We formulate an optimization problem and compare performance of multi-path routing based on bandwidth usage only with the impairment aware alternative. We show that there is a trade-off between optical signal quality and bandwidth utilization.

  • 113. McDonald, David
    et al.
    Schatz, Richard
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Mikroelektronik och tillämpad fysik, MAP. KTH, Skolan för informations- och kommunikationsteknik (ICT), Mikroelektronik och Informationsteknik, IMIT. KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik, Fotonik.
    Spano, Paolo
    O’Gorman, James
    Measurement and parameter extraction of semiconductor lasers: experiences of the pan-European action COST 2401998Ingår i: Laser Diodes and Applications III, Vol. 3415, s. 152-163Artikel i tidskrift (Refereegranskat)
  • 114.
    Monti, Paolo
    et al.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik (Stängd 20120101), Fotonik (Stängd 20120101). KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS, Optical Network Laboratory (ON Lab).
    Cavdar, Cicek
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik (Stängd 20120101), Fotonik (Stängd 20120101). KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS, Optical Network Laboratory (ON Lab). KTH, Skolan för informations- och kommunikationsteknik (ICT), Centra, KTH Center för Trådlösa System, Wireless@kth. Istanbul Technical University, Turkey.
    Chen, Jiajia
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik (Stängd 20120101), Fotonik (Stängd 20120101). KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS, Optical Network Laboratory (ON Lab).
    Wosinska, Lena
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik (Stängd 20120101), Fotonik (Stängd 20120101). KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS, Optical Network Laboratory (ON Lab).
    Fumagalli, Andrea
    The University of Texas at Dallas, US.
    New Dimensions for Survivable Service Provisioning in Optical Backbone and Access Networks2012Ingår i: Resilient Optical Network Design: Advances in Fault-Tolerant Methodologists / [ed] Mark Leeson and Yousef Kavian, IGI Global, 2012, s. 227-252Kapitel i bok, del av antologi (Refereegranskat)
    Abstract [en]

    Originally, networks were engineered to provide only one type of service, i.e. either voice or data, soonly one level of resiliency was requested. This trend has changed, and today’s approach in serviceprovisioning is quite different. A Service Level Agreement (SLA) stipulated between users and serviceproviders (or network operators) regulates a series of specific requirements, e.g., connection set-up timesand connection availability that has to be met in order to avoid monetary fines. In recent years this hascaused a paradigm shift on how to provision these services. From a “one-solution-fits-all” scenario, wewitness now a more diversified set of approaches where trade-offs among different network parameters(e.g., level of protection vs. cost and/or level of protection vs. blocking probability) play an important role.This chapter aims at presenting a series of network resilient methods that are specifically tailored for adynamic provisioning with such differentiated requirements. Both optical backbone and access networksare considered. In the chapter a number of provisioning scenarios - each one focusing on a specificQuality of Service (QoS) parameter - are considered. First the effect of delay tolerance, defined as theamount of time a connection request can wait before being set up, on blocking probability is investigatedwhen Shared Path Protection is required. Then the problem of how to assign “just-enough” resources tomeet each connection availability requirement is described, and a possible solution via a Shared PathProtection Scheme with Differentiated Reliability is presented. Finally a possible trade off between deploymentcost and level of reliability performance in Passive Optical Networks (PONs) is investigated. 

    The presented results highlight the importance of carefully considering each connection’s QoS parameterswhile devising a resilient provisioning strategy. By doing so the benefits in terms of cost saving andblocking probability improvement becomes relevant, allowing network operators and service providersto maintain satisfied customers at reasonable capital and operational expenditure levels.

  • 115.
    Monti, Paolo
    et al.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik (Stängd 20120101), Fotonik (Stängd 20120101).
    Muhammad, Ajmal
    Linköpings Tekniska Högskola.
    Cerutti, Isabella
    Scuola Superiore Sant'Anna.
    Cavdar, Cicek
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik (Stängd 20120101), Fotonik (Stängd 20120101).
    Wosinska, Lena
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik (Stängd 20120101), Fotonik (Stängd 20120101).
    Castoldi, Piero
    Scuola Superiore Sant'Anna.
    Tzanakaki, Anna
    Athens Information Technology.
    Energy-efficient lightpath provisioning in a static WDM network with dedicated path protection2011Ingår i: International Conference on Transparent Optical Networks, IEEE , 2011, s. 1-5Konferensbidrag (Refereegranskat)
    Abstract [en]

    The interest in the energy consumption of communication networks has risen in the recent years. In an effort to tackle this problem, several approaches have been presented to reduce the power consumed by the entire network infrastructure, including optical transport. Most of the solutions studied and proposed in the literature, however, pay little or no attention to the power consumed to ensure the resiliency of the overall network. In wavelength division multiplexing (WDM) networks resilient to single failures, an innovative strategy that can be adopted to reduce power consumption entails setting to sleep mode the optical devices supporting solely protection lightpaths. To take full advantage of this strategy, it is important to optimally route the lightpaths so that the number of devices supporting exclusively protection lightpaths is maximized. An optimal solution for this provisioning problem was previously presented, but features a limited scalability with the network size. This paper first proposes a scalable and efficient heuristic that chooses the route of the working and protection lightpaths with the aim to maximize the power saving. The performance of the heuristic is compared with the optimal solution and a sensitivity analysis of the drained power is carried out by considering a variety of networking scenarios. Up to 20% of the network links can be set to sleep leading to significant power saving, especially at low load and when the power consumption in sleep mode is negligible.

  • 116.
    Monti, Paolo
    et al.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik, Fotonik.
    Wiatr, Pawel
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik.
    Jirattigalachote, Amornrat
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik.
    Wosinska, Lena
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik.
    Trading Power Savings for Blocking Probabilityin Dynamically Provisioned WDM Networks2010Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    In those networking scenarios (e.g., the stationary/mobile wireless paradigm) where limited energy storagecapabilities is a limiting factor, power efficiency has been studied extensively for a long time. In the last fewyears, the steadily growing power consumption figures of ICT [1][2] along with a recent public awareness of thepossible environmental effects, broadened the focus of the research efforts towards more power conscioussolutions also for wired networks. One promising solution going in this direction is represented by transparentwavelength division multiplexing (WDM) networks, where all-optical circuits (or lightpaths) carry the networktraffic from the source to the destination node in the optical domain, i.e. without any optical-to-electrical(O-E-O) conversion. To further improve network power efficiency, several approaches have been proposed inthe literature attempting to reduce the power consumption in transparent WDM networks [3][4]. Among them,power aware (PA) routing and wavelength assignment (RWA) algorithms are receiving a lot of attention. Onepossible solution for the PA-RWA problem is to limit the number of devices in the network that need to bepowered-on to support the lightpath requests [5]. These methods, however, have an adverse impact on the lengthof the provisioned lightpaths. In order to efficiently use as much powered-on network resources as possible, thepath length is, on average, longer than the one found with traditional (and less power efficient) shortest pathsolutions. This is in contradiction with the goal of classical RWA algorithms that tend to minimize the resourceusage (i.e., wavelengths and fibers) within the network, in order to minimize the blocking probability. Whenavailability of network resources becomes something that cannot be overlooked, a trade off needs to be assessedbetween power savings and blocking probability.In this talk, a non-conventional solution to the PA-RWA problem is presented. It is based on the intuitionthat, in some cases, relaxing the power minimization constraint can have beneficial effects on the overallnetwork performance, i.e., it can contribute to the reduction of resource fragmentation in the network and, in thisway, lower the blocking probability. The proposed algorithm leverages on a cost function that considers both thepower status of network elements (in this particular case the in-line optical amplifiers on fiber links only) and theinformation about wavelength usage. The algorithm has been tested using a Pan-European core network (i.e.,COST 239). Performance results confirm the presence of a trade-off between energy saving and blockingprobability. They also suggest that a “binary” approach using only the powered-on/powered-off informationmight not always be the best choice.

  • 117. Mortensen, Niels Asger
    et al.
    Yan, Min
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik, Fotonik.
    Sigmund, Ole
    Breinbjerg, Olav
    On the unambiguous determination of effective optical properties of periodic metamaterials: a one-dimensional case study2010Ingår i: JOURNAL OF THE EUROPEAN OPTICAL SOCIETY-RAPID PUBLICATIONS, ISSN 1990-2573, Vol. 5, s. 10010-Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We show how branch ambiguities in the extraction of effective parameters is arising as a direct consequence of the underlying Bloch state physics. The mutual importance of the different branches in general depends on the experimental context, and we show how the Fourier spectrum of the field inside the metamaterial can be used to access this. Different numerical examples illustrate how a predominant branch may be identified for lambda >> a while at higher frequency the power may be distributed over more branches. This is in particular true near band-edges and strong resonances. Extensions to two- and three-dimensional metamaterial designs are discussed.

  • 118. Morthier, G.
    et al.
    Baets, R.
    Tsang, C. F.
    Caroll, J. E.
    Wenzel, H.
    Mecozzi, A.
    Sapia, A.
    Correc, P.
    Hansmann, S.
    Burkhardt, H.
    Bonello, R.
    Montrosset, I.
    Lassen, H. E.
    Olesen, H.
    Schatz, Richard
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Mikroelektronik och tillämpad fysik, MAP. KTH, Skolan för informations- och kommunikationsteknik (ICT), Mikroelektronik och Informationsteknik, IMIT. KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik, Fotonik.
    Bissessur, H.
    Vey, J-L
    Duan, G.
    Comparison of different DFB laser models within the European COST 240 collaboration1993Ingår i: Integrated Photonics Research (IPR) Palm Springs, California March 22, 1993    Semiconductor Device Modeling 1 (IWB), 1993Konferensbidrag (Refereegranskat)
  • 119. Morthier, Geert
    et al.
    Baets, Roel
    TSIGOPOULOS, A
    SPHICOPOULOS, T
    TSANG, CF
    CARROLL, JE
    WENZEL, H
    MECOZZI, A
    SAPIA, A
    CORREC, P
    HANSMANN, S
    BURKHARD, H
    PARADISI, A
    MONTROSSET, I
    OLESEN, H
    LASSEN, HE
    Schatz, Richard
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Mikroelektronik och tillämpad fysik, MAP. KTH, Skolan för informations- och kommunikationsteknik (ICT), Mikroelektronik och Informationsteknik, IMIT. KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik, Fotonik.
    BISSESSUR, H
    COMPARISON OF DIFFERENT DFB LASER MODELS WITHIN THE EUROPEAN COST-240 COLLABORATION.1994Ingår i: IEE Proceedings - Optoelectronics, ISSN 1350-2433, E-ISSN 1359-7078, Vol. 141, s. 82-88Artikel i tidskrift (Refereegranskat)
  • 120. Muhammad, A.
    et al.
    Forchheimer, Robert
    Wosinska, Lena
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik, Fotonik.
    Impairment-Aware Dynamic Provisioning in WDM Networks with Set-up Delay Tolerance and Holding-time Awareness2011Ingår i: 2011 17th IEEE International Conference on Networks (ICON), 2011, s. 213-218Konferensbidrag (Refereegranskat)
    Abstract [en]

    We study a dynamic WDM network with nonideal components in the physical layer which uses an impairment-aware routing and wavelength (RWA) algorithm for connection provisioning. We investigate the reduction in blocking probability (BP) by utilizing service Level Agreement (SLA) metric i.e. setup delay tolerance during connection provisioning. Furthermore, we explore the improvement in the network performance by efficiently utilizing the knowledge of the connections holding-time, another metric of SLA. Keeping in mind that BP reduction can be obtained by set-up delay tolerance [1] our focus is to investigate how set-up delay tolerance combined with holding-time awareness can improve BP performance caused by physical impairment. Our simulation results confirm that significant improvement can be achieved by holding-time aware connection provisioning compared to the unaware holding-time case. Moreover as expected, set-up delay tolerance can reduce BP even without knowledge of connections holding-time.

  • 121. Muhammad, Ajmal
    et al.
    Cavdar, Cicek
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik (Stängd 20120101), Fotonik (Stängd 20120101).
    Wosinska, Lena
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik (Stängd 20120101), Fotonik (Stängd 20120101).
    Forchheimer, Robert
    Effect of Delay Tolerance in WDM Networks with Differentiated Services2011Konferensbidrag (Refereegranskat)
    Abstract [en]

    We study a dynamic WDM network supporting different service classes (SC) containing applications having similar setup delay tolerance. By utilizing delay tolerance we propose scheduling strategies able to significantly reduce blocking probability of each SC.

  • 122.
    Muhammad, Ajmal
    et al.
    Linköpings tekniska högskola.
    Monti, Paolo
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik (Stängd 20120101), Fotonik (Stängd 20120101).
    Cerutti, Isabella
    Scuola Superiore Sant'Anna.
    Wosinska, Lena
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik (Stängd 20120101), Fotonik (Stängd 20120101).
    Castoldi, Piero
    Scuola Superiore Sant'Anna.
    Tzanakaki, Anna
    Athens Information Technology.
    Energy-Efficient WDM Network Planning with Dedicated Protection Resources in Sleep Mode2010Ingår i: Global Telecommunications Conference (GLOBECOM 2010), 2010 IEEE, IEEE , 2010, s. 1-5Konferensbidrag (Refereegranskat)
    Abstract [en]

    Energy-efficient optical networks are gaining momentum as environmental-friendly solutions with reduced operational costs. Energy-efficiency can be achieved by using devices in sleep mode, i.e., a low-power, inactive state in which devices can be suddenly waken-up upon occurrence of triggering events. This paper advocates a sleep mode option for the optical devices (e.g., amplifiers, optical switches) installed for protection purposes only. These devices can be put in sleep mode to reduce the network power consumption, but they can be promptly waken up (if necessary) upon a failure occurrence. This principle is proposed and applied in Wavelength Division Multiplexing (WDM) networks with dedicated-path protection to ensure survivability against single-link failures. The main contribution of the paper is the definition of the energy-efficient network planning problem for resilient WDM networks where optical devices can be configured in sleep mode. Optimal results of the integer linear programming (ILP) problem show savings of up to 25% in the overall power consumption.

  • 123.
    Naruse, Makoto
    et al.
    Natl Inst Informat & Commun Technol, Tokyo, Japan .
    Holmström, Petter
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik, Fotonik.
    Kawazoe, Tadashi
    Univ Tokyo, Tokyo, Japan .
    Akahane, Kouichi
    Natl Inst Informat & Commun Technol, Tokyo, Japan .
    Yamamoto, Naokatsu
    Natl Inst Informat & Commun Technol, Tokyo, Japan ; Univ Tokyo, Tokyo, Japan .
    Thylén, Lars
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik, Fotonik.
    Ohtsu, Motoichi
    Univ Tokyo, Tokyo, Japan .
    Energy dissipation in energy transfer mediated by optical near-field interactions and their interfaces with optical far-fields2012Ingår i: Applied Physics Letters, ISSN 0003-6951, E-ISSN 1077-3118, Vol. 100, nr 24, s. 241102-Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We theoretically and experimentally evaluated energy dissipation of nanophotonic devices based on energy transfer via near-field interactions and their interfaces with optical far-fields. The lower bound is about 10(4) times more energy-efficient than electronic devices. We also examined some fundamental differences between near-field-mediated optical energy transfer logic and electrical logic in terms of energy dissipation.

  • 124. Naruse, Makoto
    et al.
    Hori, Hirokazu
    Kobayashi, Kiyoshi
    Holmström, Petter
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik, Fotonik.
    Thylén, Lars
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik, Fotonik.
    Ohtsu, Motoichi
    Lower bound of energy dissipation in optical excitation transfer via optical near-field interactions2010Ingår i: Optics Express, ISSN 1094-4087, E-ISSN 1094-4087, Vol. 18, nr 23, s. A544-A553Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We theoretically analyzed the lower bound of energy dissipation required for optical excitation transfer from smaller quantum dots to larger ones via optical near-field interactions. The coherent interaction between two quantum dots via optical near-fields results in unidirectional excitation transfer by an energy dissipation process occurring in the larger dot. We investigated the lower bound of this energy dissipation, or the intersublevel energy difference at the larger dot, when the excitation appearing in the larger dot originated from the excitation transfer via optical near-field interactions. We demonstrate that the energy dissipation could be as low as 25 mu eV. Compared with the bit flip energy of an electrically wired device, this is about 10(4) times more energy efficient. The achievable integration density of nanophotonic devices is also analyzed based on the energy dissipation and the error ratio while assuming a Yukawa-type potential for the optical near-field interactions.

  • 125. Neff, Curtis W.
    et al.
    Andersson, L. Mauritz
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik, Fotonik.
    Qiu, Min
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Mikroelektronik och tillämpad fysik, MAP.
    Coupled resonator optical waveguide structures with highly dispersive media2007Ingår i: Optics Express, ISSN 1094-4087, E-ISSN 1094-4087, Vol. 15, nr 16, s. 10362-10369Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Analysis of photonic crystal coupled resonator optical waveguide (CROW) structures with a highly dispersive background medium is presented. A finite-difference time-domain algorithm was employed which contains an exact representation of the permittivity of a three-level atomic system which exhibits electromagnetically induced transparency (EIT). We find that the coupling strength between nearest-neighbor cavities in the CROW decreases with increasing steepness of the background dispersion, which is continuously tunable as it is directly related to the control field Rabi frequency. The weaker coupling decreases the speed of pulse propagation through the waveguide. In addition, due to the dispersive nature of the EIT background, the CROW band shape is tuned around a fixed k-point. Thus, the EIT background enables dynamic tunability of the CROW band shape and the group velocity in the structure at a fixed operating point in momentum space.

  • 126. Neff, Curtis W.
    et al.
    Andersson, L. Mauritz
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik, Fotonik.
    Qiu, Min
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Mikroelektronik och tillämpad fysik, MAP.
    Modelling electromagnetically induced transparency media using the finite-difference time-domain method2007Ingår i: New Journal of Physics, ISSN 1367-2630, E-ISSN 1367-2630, Vol. 9Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Time-domain electromagnetic modelling of complex structures which include both non-dispersive media and media exhibiting electromagnetically induced transparency (EIT) require a general, robust calculation method such as finite-difference time-domain (FDTD). We propose a complex-valued, exact two-pole representation of the permittivity of a three-level system which is suitable for integration into the FDTD algorithm via the auxiliary differential equation method. Our calculation model confirmed reported results which were calculated with an approximate representation of the EIT permittivity. Additionally, propagation calculations which mimic slow light experiments were performed. A major advantage of our representation is the ease with which changes in the control field Rabi frequency can be implemented by using a time-dependent permittivity.

  • 127.
    Neff, Curtis W.
    et al.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik, Fotonik.
    Andersson, L. Mauritz
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik, Fotonik.
    Qui, Min
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik, Fotonik.
    Enhanced Transmission in Dynamically Tuned Optical Microresonator Possessing Highly Dispersive Media2007Ingår i: ECIO European Conference on Integrated Optics 2007, 2007, s. WH4-Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    We present a theoretical study of an opticalmicroresonator system which contains a electromagneticallyinduced transparency medium within the resonator.We find that a time-dependent tuning of thedispersive properties of the resonator medium resultsin an enhanced transmission spectrum.

  • 128. Nilsson, L. -E
    et al.
    Claesson, A.
    Margulis, Walter
    KTH, Skolan för teknikvetenskap (SCI), Tillämpad fysik.
    Fonjallaz, Pierre-Yves
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik (Stängd 20120101), Fotonik (Stängd 20120101). KTH, Skolan för informations- och kommunikationsteknik (ICT), Centra, Kista Photonics Research Center, KPRC. Swiss Federal Institute of Technology, Switzerland.
    Specialty Single-Mode Fibers2007Ingår i: Specialty Optical Fibers Handbook, Elsevier, 2007, s. 165-193Kapitel i bok, del av antologi (Refereegranskat)
    Abstract [en]

    This chapter provides an overview of unusual multifunctional, specialty single-mode fibers-macrohole fibers, multicore fibers, fibers with internal electrodes, and fibers for high-temperature resistant fiber Bragg gratings. Macrohole fibers belong to the group of microstructured fibers, which encompass a wide variety of fibers with air holes or other structures extending in the axial direction. Functions performed using macrostructured fibers include supercontinuum generation in tapered hole fibers, dispersion management, fibers with decreased bend loss for compact optical fiber wiring, and fibers for polarimetric sensing, and lasers. The introduction of materials in the holes adds the possibility of manipulating the guiding properties of the fiber. This can be achieved by interaction of the guided mode with actively controllable materials in the holes or by using the inserted materials for other active functions, such as a metal electrode to implement electro-optic control of the fiber. The proposed applications for multicore fibers span over lasers and amplifiers, transport fibers for broadband communications, passive, and active fiber optic components such as filters, multiplexers, and various kinds of sensors. The ultimate multicore fiber is the image fiber used in endoscopes and other such devices.

  • 129. O'Mahony, M.
    et al.
    Politi, C.T.
    Wosinska, Lena
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik, Fotonik.
    Tzanakaki, Anna
    Mitchell, J.
    Van Daele, P.
    Key Technologies for Optical Networks2009Ingår i: International Commission for Optics: topical meeting on Emerging Trends and Novel Materials in Photonics (ICO-PHOTONICS-DELPHI2009), 2009Konferensbidrag (Refereegranskat)
  • 130. Ozturk, Z. Fatih
    et al.
    Xiao, Sanshui
    Yan, Min
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik, Fotonik.
    Wubs, Martijn
    Jauho, Antti-Pekka
    Mortensen, N. Asger
    Field enhancement at metallic interfaces due to quantum confinement2011Ingår i: J NANOPHOTONICS, ISSN 1934-2608, Vol. 5, s. 051602-Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We point out an apparently overlooked consequence of the boundary conditions obeyed by the electric displacement vector at air-metal interfaces: the continuity of the normal component combined with the quantum mechanical penetration of the electron gas in the air implies the existence of a surface on which the dielectric function vanishes. This, in turn, leads to an enhancement of the normal component of the total electric field. We study this effect for a planar metal surface, with the inhomogeneous electron density accounted for by a Jellium model. We also illustrate the effect for equilateral triangular nanoislands via numerical solutions of the appropriate Maxwell equations, and show that the field enhancement is several orders of magnitude larger than what the conventional theory predicts.

  • 131. Palkopoulou, E.
    et al.
    Meusburger, C.
    Schupke, D.
    Wosinska, Lena
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik (Stängd 20120101), Fotonik (Stängd 20120101).
    Bauschert, T.
    Combining multi-period and multi-layer network planning: Ignored potential?2010Ingår i: 36th European Conference and Exhibition on Optical Communication, ECOC 2010, 2010Konferensbidrag (Refereegranskat)
    Abstract [en]

    Multi-layer and multi-period network planning can lead to significant cost reductions. Using linear programming we study the effect of their joint consideration for IP-over-WDM networks. Case studies show cost savings surpassing 20% by including forecast knowledge in multi-layer optimization.

  • 132. Pandi, Z.
    et al.
    Wosinska, Lena
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik, Fotonik.
    On temporary inconsistency of the link state database with prompt update policies2005Ingår i: 2005 7th International Conference on Transparent Optical Networks, Vol 1, Proceedings, 2005, Vol. 1, s. 437-440Konferensbidrag (Refereegranskat)
    Abstract [en]

    Link state databases maintained in parallel at each node in networks that require link state information for proper operation try to reflect real-time changes of the network state. Information dissemination, however, by its very nature introduces latency in the update of link state information at different nodes, which may in turn lead to faulty decisions that entail additional delay perceived by user traffic. The paper presents a probabilistic model based on simple assumptions in order to derive an upper bound on the probability that such a link state database inconsistency occurs.

  • 133.
    Peroza Marval, Maria Jose
    et al.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik, Fotonik.
    Chen, Jiajia
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik, Fotonik.
    Wosinska, Lena
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik, Fotonik.
    Fumagalli, A.
    Adaptive routing based on summary information mitigates the adverse impact of outdated control messages2011Ingår i: Transparent Optical Networks (ICTON), 2011 13th International Conference on, Stockholm, 2011, s. 1-4Konferensbidrag (Refereegranskat)
    Abstract [en]

    Adaptive routing is considered as a promising solution to support flexible resource allocation in wavelength division multiplexing network. Resource advertisement protocols, such as link state advertisement (LSA), are essential to enable routing algorithms to efficiently carry out the required path computation. The LSA nonnegligible convergence time may lead to outdated link information, which in turns may adversely affect the efficiency of the computed path. As a result, traffic engineering is suboptimal and some services may be unnecessarily blocked. This study investigates the impact of outdated information on the blocking probability of adaptive routing schemes focusing on two LSA protocols: one advertising specific resource information and one advertising only a summary of the same. Our simulation results show that compared with the routing scheme requiring specific information LSA, the approach based on LSA with summary information is by its nature not precise and hence able to mitigate the adverse impact of the LSA convergence time on blocking performance.

  • 134.
    Pinos, Andrea
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik, Fotonik.
    Optical properties and degradation of deep ultraviolet AIGaN-based light-emitting diodes2011Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
  • 135.
    Qian, Jun
    et al.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik (Stängd 20120101), Fotonik (Stängd 20120101).
    Gharibi, Arash
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik (Stängd 20120101), Fotonik (Stängd 20120101).
    Li, Xin
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik (Stängd 20120101), Fotonik (Stängd 20120101).
    He, Sailing
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik (Stängd 20120101), Fotonik (Stängd 20120101).
    Organically modified silica nanoparticles with photosensitizing drugs encapsulated for photodynamic therapy2008Ingår i: Optics InfoBase Conference Papers, 2008Konferensbidrag (Refereegranskat)
    Abstract [en]

    Organically modified silica nanoparticles, doped with photosensitizers, are synthesized, characterized and used for photodynamic therapy (PDT) of cancer. These nanoparticles were uptaken by tumor cells in vitro and the effect of photon-induced toxicity was demonstrated.

  • 136.
    Qiu, Min
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik, Fotonik.
    Silicon Photonic Crystal Surface Mode Microcavities2008Ingår i: 2008 IEEE PHOTONICSGLOBAL@SINGAPORE (IPGC), VOLS 1 AND 2, NEW YORK: IEEE , 2008, s. 15-18Konferensbidrag (Refereegranskat)
    Abstract [en]

    High-Q surface mode micro-cavities in silicon-on-insulator (SOI) structures are investigated. Cavity structures in amorphous silicon based SOI structures show intrinsic Q values of 2000, while cavities in crystalline SOI structures can have intrinsic Q values larger than 10(4).

  • 137.
    Qiu, Min
    et al.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik, Fotonik. KTH, Skolan för informations- och kommunikationsteknik (ICT), Mikroelektronik och tillämpad fysik, MAP.
    Li, Qiang
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik, Fotonik. KTH, Skolan för informations- och kommunikationsteknik (ICT), Mikroelektronik och tillämpad fysik, MAP.
    Zhang, Ziyang
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Mikroelektronik och tillämpad fysik, MAP.
    Liu, Fangfei
    Chang, Qingjiang
    Su, Yikai
    Silicon micro-cavities and their system applications2009Ingår i: PHOTONICS PACKAGING, INTEGRATION, AND INTERCONNECTS IX / [ed] Glebov AL; Chen RT, 2009, Vol. 7221Konferensbidrag (Refereegranskat)
    Abstract [en]

    We experimentally demonstrate resonance-splitting and enhanced notch as a result of the mutual mode coupling in silicon ring resonator. Dense wavelength conversions, wavelength multicasting and optical up-converter are demonstrated in the split silicon ring resonator. A temporal differentiator and format conversion from NRZ to AMI are demonstrated utilizing the filtering effect of ring resonator. Photonic phase shifter and delay line are demonstrated utilizing the phase shift of ring resonator.

  • 138.
    Qiu, Min
    et al.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Mikroelektronik och tillämpad fysik, MAP.
    Ruan, Zhichao
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Mikroelektronik och tillämpad fysik, MAP.
    Berrier, Audrey
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Mikroelektronik och tillämpad fysik, MAP.
    Xiao, S S
    Mulot, M.
    Swillo, M.
    Anand, Srinivasan
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Mikroelektronik och Informationsteknik, IMIT.
    He, Sailing
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Mikroelektronik och Informationsteknik, IMIT.
    Thylen, Lars
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik, Fotonik.
    Negative refraction in semiconductor photonic crystals2005Ingår i: SEMICONDUCTOR AND ORGANIC OPTOELECTRONIC MATERIALS AND DEVICES, 2005, Vol. 5624, s. 345-352Konferensbidrag (Refereegranskat)
    Abstract [en]

    The coupling efficiency between external plane waves and the Bloch waves in photonic crystals are investigated. It is found that the coupling coefficient is highly angular dependent even for an interface between air n=l and a photonic crystal with effective index -1. It is also shown that, for point imaging by a photonic crystal slab owing to the negative refraction, the influence of the surface termination to the transmission and the imaging quality is significant. Finally, we present results demonstrating experimentally negative refraction in a two-dimensional photonic crystal.

  • 139. Raffaelli, C.
    et al.
    Wosinska, Lena
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik, Fotonik.
    Andriolli, N.
    Callegati, F.
    Castoldi, P.
    Kabacinski, W.
    Maier, G.
    Pattavina, A.
    Valcarenghi, L.
    Photonics in Switching in NoE e-Photon/One+2007Ingår i: ICTON 2007: Proceedings of the 9th International Conference on Transparent Optical Networks, Vol 1 / [ed] Marciniak, M, 2007, Vol. 1, s. 167-170Konferensbidrag (Refereegranskat)
    Abstract [en]

    The exploitation of photonic technology through application of switching principles and system concepts in switch implementation, i.e. photonics in switching, is a very challenging topic in the field of optical networking research. Many European research teams have been involved in high quality studies and trials in this field since several years and obtained funding opportunities for joining their expertise within the e-photon/One+ Network of Excellence. This talk aims at presenting how collaborations on photonics in switching research has been organized within e-Photon/One+ and which actions have been finalized for exploitation and dissemination of this knowledge in science and education. The paper will report a description of research contributions from different partners involved in photonics in switching research.

  • 140. Razo, M.
    et al.
    Billenahalli, S.
    Huang, W.
    Sivasankaran, A.
    Tang, L.
    Vardhan, H.
    Tacca, M.
    Fumagalli, A.
    Monti, Paolo
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik (Stängd 20120101), Fotonik (Stängd 20120101).
    Lee, Y.
    Liu, X.
    Sui, Z.
    Design of hierarchical WDM networks2009Ingår i: Network Architectures, Management, and Applications VII, SPIE - International Society for Optical Engineering, 2009, s. 76331I-Konferensbidrag (Refereegranskat)
    Abstract [en]

    Hierarchical (multi-core) Wavelength Division Multiplexing (WDM) networks present a challenging design problem to the network designer who wishes to establish all-optical circuits end-to-end and across multiple network cores. Due to the nature of the hierarchical structure and its traffi distribution, it is likely that the inner core requires more capacity when compared to the capacity required by the metro cores, which are individually connected to the inner core. This capacity mismatch cannot be addressed by assigning distinct transmission rates to each core, as this solution would result in using electronic time division add-drop multiplexer to interconnect the traffi across cores with distinct rates. An alternative solution to addressing the capacity mismatch between WDM metro and inner core is explored in this paper, which is based on a limited number of wavelengths (a subset of the full set) being used in the metro core, when compared to the full set of wavelengths being used in the inner core. Two available architectures are presented in the paper, discussing their respective advantages and disadvantages.

  • 141.
    Razo, Miguel
    et al.
    The University of Texas at Dallas.
    Arie, Litovsky
    The University of Texas at Dallas.
    Sivasankaran, Arularasi
    The University of Texas at Dallas.
    Tang, Limin
    The University of Texas at Dallas.
    Vardhan, Hars
    The University of Texas at Dallas.
    Monti, Paolo
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik (Stängd 20120101), Fotonik (Stängd 20120101).
    Tacca, Marco
    The University of Texas at Dallas.
    Fumagalli, Andrea
    The University of Texas at Dallas.
    Demonstrating the PlaNet-PTN Module: a Single Layer Design Tool for Packet Transport Networks2009Ingår i: IEEE Conference on Computer Communications (INFOCOM), 2009Konferensbidrag (Refereegranskat)
    Abstract [en]

    PlaNet is a multilayer network planning tool developed at the University of Texas at Dallas. This demo willillustrate some of the features of PlaNet-PTN, one of the modulesavailable in the PlaNet tool. PlaNet-PTN can be used to designand plan a single layer packet transport network (PTN). Qualityof protection, routing constraints, minimization of the networkequipment cost, and user’s desired run time of the tool are justsome examples of the features available in PlaNet. As shown inthe demo, the PlaNet-PTN planning module is able to provide,among others, optimization of LSP-tunnel routes, link capacityplacement, node and link equipment configuration.

  • 142.
    Razo, Miguel
    et al.
    The University of Texas at Dallas.
    Billenahalli, Shreejith
    The University of Texas at Dallas.
    Huang, Wanjun
    The University of Texas at Dallas.
    Sivasankaran, Arularasi
    The University of Texas at Dallas.
    Tang, Limin
    The University of Texas at Dallas.
    Vardhan, Hars
    The University of Texas at Dallas.
    Monti, Paolo
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik (Stängd 20120101), Fotonik (Stängd 20120101).
    Tacca, Marco
    The University of Texas at Dallas.
    Fumagalli, Andrea
    The University of Texas at Dallas.
    Limiting Wavelength Converter Usage in Resilient WDM Networks2010Ingår i: 2010 IEEE INTERNATIONAL CONFERENCE ON COMMUNICATIONS, 2010Konferensbidrag (Refereegranskat)
    Abstract [en]

    A careful wavelength assignment (WA) to lambda services must be performed to reduce the total number of wavelength converters (WCs) that are required when the wavelength continuity constraint cannot be met in wavelength division multiplexing (WDM) networks. With the successful introduction of reconfigurable optical add-drop multiplexers (ROADMs), WDM networks are now growing in size, both in the number of optical nodes and the number of wavelengths supported. Fast and memory efficient WA algorithms are required to design cost effective large WDM networks. This paper presents a scalable and efficient WA heuristic algorithm aimed at reducing the total number of WCs that are required in (large) WDM networks bearing static lambda services. The WA algorithm is applied to both unprotected and (dedicated) protected lambda services. In the latter case, the wavelength continuity constraint between the working and protection path of a lambda service is taken into consideration when non-tunable optical transceivers are employed.

  • 143.
    Razo, Miguel
    et al.
    The University of Texas at Dallas.
    Billenahalli, Shreejith
    The University of Texas at Dallas.
    Huang, Wanjun
    The University of Texas at Dallas.
    Sivasankaran, Arularasi
    The University of Texas at Dallas.
    Tang, Limin
    The University of Texas at Dallas.
    Vardhan, Hars
    The University of Texas at Dallas.
    Tacca, Marco
    The University of Texas at Dallas.
    Fumagalli, Andrea
    The University of Texas at Dallas.
    Monti, Paolo
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik (Stängd 20120101), Fotonik (Stängd 20120101).
    Lee, Young
    Huawei.
    Liu, Xinchao
    Huawei.
    Sui, Zhicheng
    Huawei.
    Design of hierarchical WDM networks2009Ingår i: 2009 Asia Communications and Photonics Conference and Exhibition, ACP 2009, 2009, Vol. 2009-SupplementKonferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    Hierarchical (multi-core) Wavelength Division Multiplexing (WDM) networks present a challenging design problem to the network designer who wishes to establish all-optical circuits end-to-end and across multiple network cores. Due to the nature of the hierarchical structure and its traffi distribution, it is likely that the inner core requires more capacity when compared to the capacity required by the metro cores, which are individually connected to the inner core. This capacity mismatch cannot be addressed by assigning distinct transmission rates to each core, as this solution would result in using electronic time division add-drop multiplexer to interconnect the traffi across cores with distinct rates. An alternative solution to addressing the capacity mismatch between WDM metro and inner core is explored in this paper, which is based on a limited number of wavelengths (a subset of the full set) being used in the metro core, when compared to the full set of wavelengths being used in the inner core. Two available architectures are presented in the paper, discussing their respective advantages and disadvantages.

  • 144.
    Razo, Miguel
    et al.
    The University of Texas at Dallas.
    Litovsky, Arie
    The University of Texas at Dallas.
    Huang, Wanjun
    The University of Texas at Dallas.
    Sivasankaran, Arularasi
    The University of Texas at Dallas.
    Tang, Limin
    The University of Texas at Dallas.
    Vardhan, Hars
    The University of Texas at Dallas.
    Monti, Paolo
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik (Stängd 20120101), Fotonik (Stängd 20120101).
    Tacca, Marco
    The University of Texas at Dallas.
    Fumagalli, Andrea
    The University of Texas at Dallas.
    The PlaNet-PTN Module: a Single Layer Design Tool for Packet Transport Networks2009Ingår i: CAMAD: 2009 IEEE 14TH INTERNATIONAL WORKSHOP ON COMPUTER AIDED MODELING AND DESIGN OF COMMUNICATION LINKS AND NETWORKS, 2009, s. 74-78Konferensbidrag (Refereegranskat)
    Abstract [en]

    PlaNet is a multilayer network planning tool developed at the University of Texas at Dallas. This paper illustrates some of the features of PlaNet-PTN, one of the modules available in the PlaNet tool. PlaNet-PTN can be used to design and plan a single layer packet transport network (PTN). Quality of protection, routing constraints, minimization of the network equipment cost, and user’s desired run time of the tool are just some examples of the features available in PlaNet. As shown in the paper, the PlaNet-PTN planning module is able to provide, among others, optimization of Label Switched Path (LSP) routes, link capacity placement, node and link equipment configuration.

  • 145. Rong, Y.
    et al.
    Ge, Y.
    Huo, Y.
    Fiorentino, M.
    Kamins, T. I.
    Ochalski, T.
    Thylén, Lars
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik (Stängd 20120101), Fotonik (Stängd 20120101).
    Chacinski, Marek
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik (Stängd 20120101), Fotonik (Stängd 20120101).
    Harris, J. S.
    High speed optical modulation in Ge quantum wells using quantum confined stark effect2009Ingår i: Group IV Photonics, 2009. GFP '09. 6th IEEE International Conference on, 2009, s. 157-159Konferensbidrag (Refereegranskat)
    Abstract [en]

    We designed the coplanar high-speed modulator with Ge/SiGe quantum wells, and demonstrated 25GHz of modulation with 3.125GHz of eye diagram using quantum-confined stark effect.

  • 146. Sambaraju, R.
    et al.
    Herrera, J.
    Marti, J.
    Zibar, D.
    Caballero, A.
    Jensen, J. B.
    Monroy, I. T.
    Westergren, Urban
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik (Stängd 20120101), Fotonik (Stängd 20120101).
    Walber, A.
    Up to 40 Gb/s wireless signal generation and demodulation in 75-110 GHz band using photonic techniques2010Ingår i: Proceedings - 2010 IEEE International Topical Meeting on Microwave Photonics, MWP 2010, 2010Konferensbidrag (Refereegranskat)
    Abstract [en]

    Record wireless signal capacity of up to 40 Gb/s is demonstrated in the 75-110 GHz band. All-optical OFDM and photonic up-conversion are used for generation and digital coherent detection for demodulation.

  • 147. Silfvenius, C.
    et al.
    Swillo, M.
    Claesson, J.
    Forsberg, E.
    Akram, N.
    Chacinski, Marek
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik (Stängd 20120101), Fotonik (Stängd 20120101).
    Thylén, Lars
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik (Stängd 20120101). KTH, Skolan för informations- och kommunikationsteknik (ICT), Centra, Kista Photonics Research Center, KPRC.
    InP-based monolithically integrated 1310/1550nm diplexer/triplexer2008Ingår i: Proceedings of SPIE - The International Society for Optical Engineering, 2008Konferensbidrag (Refereegranskat)
    Abstract [en]

    We demonstrate a low cost, non-butt-joint, wide-gain integrated device comprising 1550nm lasers, wavelength selective couplers and 1310nm sensitive photodiodes for diplexer arrays for FTTH use.

  • 148. Skorin-Kapov, Nina
    et al.
    Chen, Jiajia
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik, Fotonik.
    Wosinska, Lena
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik, Fotonik.
    A New Approach to Optical Networks Security: Attack-Aware Routing and Wavelength Assignment2010Ingår i: IEEE/ACM Transactions on Networking, ISSN 1063-6692, E-ISSN 1558-2566, Vol. 18, nr 3, s. 750-760Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Security issues and attack management in transparent wavelength division multiplexing (WDM) optical networks have become of prime importance to network operators due to the high data rates involved and the vulnerabilities associated with transparency. Deliberate physical-layer attacks, such as high-powered jamming, can seriously degrade network performance and must be dealt with efficiently. While most approaches are focused on the developing fast detection and reaction mechanisms triggered in case of an attack, we propose a novel approach to help deal with these issues in the network planning and provisioning process as a prevention mechanism. Namely, we propose to route lightpaths in such a way as to minimize the potential damage caused by various physical-layer attacks. We present a new objective criterion for the routing and wavelength assignment (RWA) problem, which we call the maximum Lightpath Attack Radius (maxLAR), and formulate the routing subproblem as an integer linear program (ILP). We test it on small networks to get an insight into its complexity and compare it to a formulation that minimizes congestion. Results indicate that our formulation achieves significantly better results for the maxLAR while obtaining near-optimal or optimal congestion in all cases. For larger networks, we propose a tabu search algorithm for attack-aware lightpath routing, in combination with an existing graph-coloring algorithm for wavelength assignment. Testing and comparing with existing approaches from literature indicate its superiority with respect to the maxLAR and average lightpath load, albeit at the expense of somewhat higher congestion. However, this is justified with the obtained improvement in network security.

  • 149.
    Skorin-Kapov, Nina
    et al.
    Zagreb University.
    Chen, Jiajia
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Mikroelektronik och tillämpad fysik, MAP.
    Wosinska, Lena
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik, Fotonik.
    A tabu search algorithm for attack-aware lightpath routing2008Ingår i: ICTON 2008: PROCEEDINGS OF 2008 10TH ANNIVERSARY INTERNATIONAL CONFERENCE ON TRANSPARENT OPTICAL NETWORKS, VOL 3 / [ed] Marciniak, M, NEW YORK: IEEE , 2008, s. 42-45Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    Attacks in Transparent Optical Networks present a serious security threat to Successful network operation due to the high data rates involved and the vulnerabilities associated with transparency. Typical physical layer attacks can involve injecting high-powered jamming signals on legitimate data channels to exploit Vulnerabilities in optical components Such as crosstalk in switches and fibers, and gain competition in amplifiers. To assure a certain quality of service in the network, we propose a novel approach which considers Such security threats during the network planning process. More specifically, we propose a tabu search heuristic aimed to perform lightpath routing in Such a way as to minimize the possible 'reachability' of a jamming attack with respect to gain competition and inter-channel crosstalk. In this way we limit the worst case scenario which can potentially be caused by such an attack. We tested the algorithm on the 14-node NSF network and compare with shortest path routing. The algorithm not only yields better attack protection, but reduces lightpath congestion and minimizes the upper bound on the number of wavelengths needed for wavelength assignment.

  • 150. Skubic, Björn
    et al.
    Chen, Biao
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik (Stängd 20120101), Fotonik (Stängd 20120101). Zhejiang University, China.
    Chen, Jiajia
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik (Stängd 20120101), Fotonik (Stängd 20120101).
    Ahmed, Jawwad
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik (Stängd 20120101), Fotonik (Stängd 20120101).
    Wosinska, Lena
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Fotonik och optik (Stängd 20120101), Fotonik (Stängd 20120101).
    Improved scheme for estimating T-CONT bandwidth demand in status reporting DBA for NG-PON2009Ingår i: Network Architectures, Management, and Applications VII, SPIE - International Society for Optical Engineering, 2009, s. 76330E-Konferensbidrag (Refereegranskat)
    Abstract [en]

    A scheme for estimating T-CONT bandwidth demand within dynamic bandwidth allocation (DBA) for next-generation passive optical network (NG-PON) is proposed and evaluated. Estimating T-CONT bandwidth demand is considered as a main challenge in gigabit-capable passive optical network (GPON) DBA. The proposed minimum guaranteed T-CONT content (MGTC) scheme allows for a more conservative estimate of bandwidth demand. It is shown that at high load significant improvements in delay, jitter and bandwidth utilization can be achieved with the proposed scheme. For light loads the conventional scheme shows better delay performance. However, this may be overcome by controlled overgranting in the MGTC scheme.

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