Resonant quantum efficiency enhancement of midwave infrared nBn photodetectors using one-dimensional plasmonic gratings
Abstract
We demonstrate up to 39% resonant enhancement of the quantum efficiency (QE) of a low dark current nBn midwave infrared photodetector with a 0.5 μm InAsSb absorber layer. The enhancement was achieved by using a 1D plasmonic grating to couple incident light into plasmon modes propagating in the plane of the device. The plasmonic grating is composed of stripes of deposited amorphous germanium overlaid with gold. Devices with and without gratings were processed side-by-side for comparison of their QEs and dark currents. The peak external QE for a grating device was 29% compared to 22% for a mirror device when the illumination was polarized perpendicularly to the grating lines. Additional experiments determined the grating coupling efficiency by measuring the reflectance of analogous gratings deposited on bare GaSb substrates.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Jun 29, 2015
- Source ID
- 10.1063/1.4923404
Entities
People
- Chadwick L. Canedy
- Chase T Ellis
- Chul Soo Kim
- Edward H. Aifer
- Eric M. Jackson
- I. Vurgaftman
- Jerry R. Meyer
- Jill A. Nolde
- Joseph G Tischler
- Joshua Abell
- Mijin Kim
- Orest. J. Glembocki
Organizations
- Office of Naval Research
- United States Naval Research Laboratory