Abstract
Narrow-bandgap semiconductors such as alloys of InAsAlSb and their heterostructures are considered promising candidates for next generation infrared photodetectors and devices. The prospect of actively tuning the spectral responsivity of these detectors at the pixel level is very appealing. In principle, this could be achieved with a tunable metasurface fabricated monolithically on the detector pixel. Here, we present first steps towards that goal using a complementary metasurface strongly coupled to an epsilon-near-zero (ENZ) mode operating in the long-wave region of the infrared spectrum. We fabricate such a coupled system using the same epitaxial layers used for infrared pixels in a focal plane array and demonstrate the existence of ENZ modes in high mobility layers of InAsSb. We confirm that the coupling strength between the ENZ mode and the metasurface depends on the ENZ layer thickness and demonstrate a transmission modulation on the order of 25%. We further show numerically the expected tunable spectral behavior of such coupled system under reverse and forward bias, which could be used in future electrically tunable detectors.
| Original language | English |
|---|---|
| Pages (from-to) | 21512-21520 |
| Number of pages | 9 |
| Journal | Optics Express |
| Volume | 24 |
| Issue number | 19 |
| DOIs | |
| State | Published - Sep 19 2016 |
| Externally published | Yes |
Funding
U.S. Department of Energy Office of Basic Energy Sciences; Laboratory Directed Research and Development; Center for Integrated Nanotechnologies; Sandia National Laboratories (DE-AC04-94AL85000). The theory and design part of this work was supported by the U.S. Department of Energy, Office of Basic Energy Sciences, Division of Materials Sciences and Engineering and by Sandia's Laboratory Directed Research and Development program. The experimental work was supported by Sandia's Laboratory Directed Research and Development program and performed, in part, at the Center for Integrated Nanotechnologies, an Office of Science User Facility operated for the U.S. Department of Energy (DOE) Office of Science. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.