Article ID Journal Published Year Pages File Type
1785000 Infrared Physics & Technology 2009 6 Pages PDF
Abstract
We report two approaches using Quantum Well Infrared Photodetectors for detection in the [3-4.2 μm] atmospheric window. Taking advantage of the large band gap discontinuity we demonstrated a strained AlInAs/InGaAs heterostructure on InP. The optical coupling in this structure has been experimentally and numerically investigated. The results show that the coupling is mainly due to guided modes. The second approach is based on double barrier strained AlGaAs/AlAs/GaAs/InGaAs active layers on GaAs. The segregation of the elements III in these structures has been investigated using a transmission electron microscope. The results show a strong modification of the conduction band profile. We demonstrate peak wavelengths at 3.9 μm for the InP based detector and 4.0 μm for the GaAs based detector. We report a background limited peak detectivity (2π field of view, 300 K background) at 4.0 μm of about 2 × 1011 cm Hz1/2 W−1 at 77 K, and 1.5 × 1011 cm Hz1/2 W−1 at 100 K.
Related Topics
Physical Sciences and Engineering Physics and Astronomy Atomic and Molecular Physics, and Optics
Authors
, , , , , ,