Change search
ReferencesLink to record
Permanent link

Direct link
Impact of feature-size dependent etching on the optical properties of photonic crystal devices
KTH, School of Information and Communication Technology (ICT), Microelectronics and Applied Physics, MAP.
Ecole Polytech Fed Lausanne, Lab Optoelect & Mat Mol.
Ecole Polytech Fed Lausanne, Inst Photon Elect Quant.
Show others and affiliations
2008 (English)In: Journal of Applied Physics, ISSN 0021-8979, E-ISSN 1089-7550, Vol. 103, no 9, 096106-1-096106-3 p.Article in journal (Refereed) Published
Abstract [en]

Feature size dependence in Ar/Cl-2 chemically assisted ion beam etching of InP-based photonic crystals (PhCs) and its influence on the optical properties of PhC devices operating in the band gap are investigated. The analysis of the measured quality factors, the determined mirror reflectivities, and losses of one-dimensional Fabry-Perot cavities clearly demonstrates the importance of feature-size dependent etching. The optical properties show a dramatic improvement up to a hole depth of about 3.5 mu m that is primarily due to a significant reduction in extrinsic losses. However, beyond this hole depth, the improvement is at a lower rate, which suggests that extrinsic losses, although present, are not dominant.

Place, publisher, year, edition, pages
2008. Vol. 103, no 9, 096106-1-096106-3 p.
Keyword [en]
National Category
Physical Sciences
URN: urn:nbn:se:kth:diva-8377DOI: 10.1063/1.2913168ISI: 000255983200189ScopusID: 2-s2.0-43949097571OAI: diva2:13682
QC 20100707. Uppdaterad från in press till published (20100707). Tidigare titel: Impact of feature size dependence on the optical properties of two-dimensional photonic crystal devices.Available from: 2008-05-08 Created: 2008-05-08 Last updated: 2010-07-07Bibliographically approved
In thesis
1. InP-based photonic crystals: Processing, Material properties and Dispersion effects
Open this publication in new window or tab >>InP-based photonic crystals: Processing, Material properties and Dispersion effects
2008 (English)Doctoral thesis, comprehensive summary (Other scientific)
Abstract [en]

Photonic crystals (PhCs) are periodic dielectric structures that exhibit a photonic bandgap, i.e., a range of wavelength for which light propagation is forbidden. The special band structure related dispersion properties offer a realm of novel functionalities and interesting physical phenomena. PhCs have been manufactured using semiconductors and other material technologies. However, InP-based materials are the main choice for active devices at optical communication wavelengths. This thesis focuses on two-dimensional PhCs in the InP/GaInAsP/InP material system and addresses their fabrication technology and their physical properties covering both material issues and light propagation aspects.

Ar/Cl2 chemically assisted ion beam etching was used to etch the photonic crystals. The etching characteristics including feature size dependent etching phenomena were experimentally determined and the underlying etching mechanisms are explained. For the etched PhC holes, aspect ratios around 20 were achieved, with a maximum etch depth of 5 microns for a hole diameter of 300 nm. Optical losses in photonic crystal devices were addressed both in terms of vertical confinement and hole shape and depth. The work also demonstrated that dry etching has a major impact on the properties of the photonic crystal material. The surface Fermi level at the etched hole sidewalls was found to be pinned at 0.12 eV below the conduction band minimum. This is shown to have important consequences on carrier transport. It is also found that, for an InGaAsP quantum well, the surface recombination velocity increases (non-linearly) by more than one order of magnitude as the etch duration is increased, providing evidence for accumulation of sidewall damage. A model based on sputtering theory is developed to qualitatively explain the development of damage.

The physics of dispersive phenomena in PhC structures is investigated experimentally and theoretically. Negative refraction was experimentally demonstrated at optical wavelengths, and applied for light focusing. Fourier optics was used to experimentally explore the issue of coupling to Bloch modes inside the PhC slab and to experimentally determine the curvature of the band structure. Finally, dispersive phenomena were used in coupled-cavity waveguides to achieve a slow light regime with a group index of more than 180 and a group velocity dispersion up to 10^7 times that of a conventional fiber.

Place, publisher, year, edition, pages
Stockholm: KTH, 2008. xv, 115 p.
Trita-ICT/MAP AVH, ISSN 1653-7610 ; 2008:7
Photonic crystals, indium phosphide, photonic bandgap, Bloch modes, slow light, dispersion, coupled cavity waveguides, chemically assisted ion beam etching, lag effect, cavities, optical losses, carrier transport, carrier lifetimes, negative refraction, photonic bandstructure
National Category
Physical Sciences
urn:nbn:se:kth:diva-4734 (URN)978-91-7178-969-3 (ISBN)
Public defence
2008-05-30, N1, Electrum 3, Kista, 10:00
QC 20100712Available from: 2008-05-08 Created: 2008-05-08 Last updated: 2010-07-12Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full textScopus

Search in DiVA

By author/editor
Berrier, AudreyAnand, Srinivasan
By organisation
Microelectronics and Applied Physics, MAP
In the same journal
Journal of Applied Physics
Physical Sciences

Search outside of DiVA

GoogleGoogle Scholar
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Altmetric score

Total: 71 hits
ReferencesLink to record
Permanent link

Direct link