Share Email Print
cover

Proceedings Paper

Design of a silicon polarization grating with a sub-wavelength anisotropic structure
Format Member Price Non-Member Price
PDF $14.40 $18.00

Paper Abstract

Polarization gratings, which have the important properties of being highly efficient for first order diffraction and having high polarization sensitivity, can be applied to beam splitters, displays, spectro-polarimeters, and so on. Usually, polarization gratings are fabricated utilizing the periodic anisotropy of liquid crystal molecules. However, high tolerance to light, heat, and humidity is required, in particular, for optical communication applications. Therefore, a polarization grating based on an inorganic material is more suitable than one based on an organic one. We propose a silicon polarization grating with form birefringence induced by an anisotropic surface microstructure with features shorter than the wavelength of light (sub-wavelength anisotropic structure), allowing the birefringence to be controlled through selection of the dimensions of the periodic structure. In this paper, we describe the design of sub-wavelength structures of half wave plates using a thin film of silicon. By optimizing the line width, the line spacing, and the thickness of the film, a transmittance of more than 99% at an incident wavelength of 1550 nm was obtained. A polarization grating based on this half wave plate was designed. The orientation of the half wave plate structure was rotated in a particular direction. Furthermore, we evaluated the wavelength dependence and incident angle dependence of the diffraction efficiency using a finite-difference time-domain method.

Paper Details

Date Published: 1 March 2016
PDF: 7 pages
Proc. SPIE 9750, Integrated Optics: Devices, Materials, and Technologies XX, 97501P (1 March 2016); doi: 10.1117/12.2211990
Show Author Affiliations
Koji Anju, Keio Univ. (Japan)
Hiroyuki Tsuda, Keio Univ. (Japan)
Hisato Uetsuka, National Institute of Advanced Industrial Science and Technology (Japan)


Published in SPIE Proceedings Vol. 9750:
Integrated Optics: Devices, Materials, and Technologies XX
Jean-Emmanuel Broquin; Gualtiero Nunzi Conti, Editor(s)

© SPIE. Terms of Use
Back to Top