Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Transmission of Infrared Radiation Through Metallic Photonic Crystal Structures
KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Optics and Photonics, OFO.ORCID iD: 0000-0001-5170-265X
KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Optics and Photonics, OFO.
2013 (English)In: IEEE Photonics Journal, ISSN 1943-0655, Vol. 5, no 5, 4500608- p.Article in journal (Refereed) Published
Abstract [en]

Monolithic integration of a metallic photonic crystal (mPhC) structure onto semiconductor infrared (IR) photodetectors can enhance the detector performances. In order to experimentally investigate the parameters involved in optimizing the transmission spectra of the mPhC structures matching the detector operating wavelength in mid- and long-wave IR (MWIR and LWIR) regimes, square thin gold (Au) hole arrays having periodicities of 4.0, 3.6, 2.4, and 1.8 mu m with various fill factors were fabricated on Si or GaAs substrates in a wafer scale. The thicknesses of the Au films are 50, 100, and 200 nm, respectively. Through this systemic study, suitable mPhC structures were revealed that can be readily integrated onto our type-II InGaSb-based quantum dot MWIR and LWIR photodetectors.

Place, publisher, year, edition, pages
2013. Vol. 5, no 5, 4500608- p.
Keyword [en]
Infrared photodetectors, plasmonics, subwavelength structures, metallic photonic crystal
National Category
Engineering and Technology
Identifiers
URN: urn:nbn:se:kth:diva-133530DOI: 10.1109/JPHOT.2013.2278527ISI: 000325410400012Scopus ID: 2-s2.0-84885642400OAI: oai:DiVA.org:kth-133530DiVA: diva2:662412
Funder
VinnovaKnowledge FoundationSwedish Foundation for Strategic Research Swedish Research Council
Note

QC 20131107

Available from: 2013-11-07 Created: 2013-11-06 Last updated: 2015-05-19Bibliographically approved
In thesis
1. Micro- and Nano-structured Metal Films for Optoelectronic Devices
Open this publication in new window or tab >>Micro- and Nano-structured Metal Films for Optoelectronic Devices
2014 (English)Licentiate thesis, comprehensive summary (Other academic)
Abstract [en]

Two types of micro and nanostructures of metal-dielectric films have been explored with the intention of improving optoelectronic devices.

The first part of the thesis concerns the design, fabrication and characterization of a metallic photonic crystal (mPhC). The mPhC was investigated with respect to fill factor, pitch size, metal thickness and bulk material to improve potential detectivity and responsivity when integrated on quantum dot infrared photo detectors (QDIPs). The pitch size was found to be the most important factor for the peak wavelength position of the bandpass while the bandwidth of the bandpass is formed by the combination of fill factor and metal thickness. The choice of substrate material was shown to only have a slight effect on the peak wavelength position through a positive relation with the refractive index of the substrate material.

In the second part of the thesis a thin-film multilayer optical resonator structure is explored with regards to its suitability as a transparent conductor. The structure was designed with a transfer matrix method. The figure of merit given by the transmissivity-over-resistance of the fabricated structure was shown to compare favorably to the notably common indium-tin-oxide (ITO) alloy currently used in optoelectronic applications as a transparent conductor. Although limited in transmission bandwidth, the silver-based multilayer structure can be valuable for optoelectronic applications and potentially replacing ITO owing to its relatively high peak transmissivity, improved conductivity as well as decreased fabrication costs.

Place, publisher, year, edition, pages
Stockholm: KTH Royal Institute of Technology, 2014. iv, 44 p.
Series
TRITA-ICT/MAP, 2014:09
National Category
Atom and Molecular Physics and Optics
Identifiers
urn:nbn:se:kth:diva-145024 (URN)978-91-7595-152-2 (ISBN)
Presentation
2014-05-27, Sal/Hall E, KTH - ICT, Isafjordsgatan 39, Kista, 14:00 (English)
Opponent
Supervisors
Note

QC 20140516

Available from: 2014-05-16 Created: 2014-05-06 Last updated: 2014-05-16Bibliographically approved
2. Structured Metallic Films for Enhanced Light Transmission and Absorption
Open this publication in new window or tab >>Structured Metallic Films for Enhanced Light Transmission and Absorption
2015 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Photonic devices such as light emitters, detectors, solar cells etc. are playing increasingly important roles in modern society. Yet their structures and designs are still under constant improvement, driven mostly by advances in material science and progress in integration techniques. A common challenge in these devices is to precisely manage transmission and absorption of light when it enters or escapes active regions. In certain devices it is even required to have both high optical transmission as well as high electrical conductivity. The current thesis investigates how structured metallic films can be devised to meet these challenges. Our work demonstrates that nanostructured noble metals can be tailored as either transparent or highly absorptive at wavelengths of interest, with or without electrical conductivity.In the first part of this work, metallic photonic crystals in the form of a thin gold film with an array of holes were fabricated with various geometrical parameters (hole size, pitch and metal thickness) on different substrate materials to investigate the impact of each parameter on the transmittance spectra at mid- to long-wave infrared wavelengths. Pitch size is shown to be the dominating factor for the high-transmittance band positions. Fill factor and metal thickness collectively define the selectivity of the pass bands. The selective transmission of infrared light can be used to improve the performance of infrared detectors. In the second part of this work, a thin-film multilayer structure based on two coupled metal-insulator-metal optical resonators was investigated for achieving a transparent conductor at visible wavelength range. The fabricated silver-based sample has a figure of merit (transmissivity-over-resistance) comparable to that of the traditionally used indium tin oxide. Such structures can potentially be used in light-emitting diodes and displays. In the third part of this work, a thin gold nanoparticle layer is obtained from a thermal annealing process. The interplay between this nanoparticle layer and a substrate metal reflector gives rise to broadband extinction of light at the near-infrared wavelength range. Specular and diffuse reflectances were singled out. Samples with high absorption or high diffuse reflection are identified. The structures can potentially be incorporated in solar cells as diffuse back reflectors or as spectrally selective absorbers for solar thermal collectors. In the fourth part of this work, the possibility of using a metal-insulator-metal structure (based on titanium, alumina, and aluminum) for achieving artificial coloration is explored. Through a diffusion-assisted deposition procedure, the dielectric spacer has a laterally varying thickness. Thereby the sample exhibits a continuum of visible colors. The reflectance spectra of the fabricated sample in the visible range were measured, and agreement to theoretical calculation is found to be very good. The artificial colors can be patterned at various geometries. Their potential application, besides functioning as spectrally selective absorbers in optoelectronic devices, can be used for security applications of consumer and artistic products.

Place, publisher, year, edition, pages
Stockholm: KTH Royal Institute of Technology, 2015. vi, 74 p.
Series
TRITA-ICT/MAP AVH, ISSN 1653-7610 ; 2015:04
National Category
Nano Technology Atom and Molecular Physics and Optics
Research subject
Physics; Information and Communication Technology
Identifiers
urn:nbn:se:kth:diva-166706 (URN)978-91-7595-519-3 (ISBN)
Public defence
2015-06-02, Sal C, Electrum, KTH-ICT, ISAFJORDSGATAN 22, Kista, 10:00 (English)
Opponent
Supervisors
Note

QC 20150519

Available from: 2015-05-19 Created: 2015-05-13 Last updated: 2015-05-19Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full textScopus

Authority records BETA

Soltanmoradi, Reyhaneh

Search in DiVA

By author/editor
Soltanmoradi, ReyhanehQiu, Min
By organisation
Optics and Photonics, OFO
Engineering and Technology

Search outside of DiVA

GoogleGoogle Scholar

doi
urn-nbn

Altmetric score

doi
urn-nbn
Total: 101 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf