| Title: |
Evidence for a defect level above the conduction band edge of InAs/InAsSb type-II superlattices for applications in efficient infrared photodetectors |
| Authors: |
Prins, A. D.; Lewis, M. K.; Bushell, Z. L.; Sweeney, S. J.; Liu, S.; Zhang, Y.-H. |
| Source: |
Applied Physics Letters ; volume 106, issue 17 ; ISSN 0003-6951 1077-3118 |
| Publisher Information: |
AIP Publishing |
| Publication Year: |
2015 |
| Description: |
We report pressure-dependent photoluminescence (PL) experiments under hydrostatic pressures up to 2.16 GPa on a mid-wave infrared InAs/InAs0.86Sb0.14 type-II superlattice (T2SL) structure at different pump laser excitation powers and sample temperatures. The pressure coefficient of the T2SL transition was found to be 93 ± 2 meV·GPa−1. The integrated PL intensity increases with pressure up to 1.9 GPa then quenches rapidly indicating a pressure induced level crossing with the conduction band states at ∼2 GPa. Analysis of the PL intensity as a function of excitation power at 0, 0.42, 1.87, and 2.16 GPa shows a clear change in the dominant photo-generated carrier recombination mechanism from radiative to defect related. From these data, evidence for a defect level situated at 0.18 ± 0.01 eV above the conduction band edge of InAs at ambient pressure is presented. This assumes a pressure-dependent energy shift of −11 meV·GPa−1 for the valence band edge and that the defect level is insensitive to pressure, both of which are supported by an Arrhenius activation energy analysis. |
| Document Type: |
article in journal/newspaper |
| Language: |
English |
| DOI: |
10.1063/1.4919549 |
| DOI: |
10.1063/1.4919549/14312175/171111_1_online.pdf |
| Availability: |
https://doi.org/10.1063/1.4919549; https://pubs.aip.org/aip/apl/article-pdf/doi/10.1063/1.4919549/14312175/171111_1_online.pdf |
| Accession Number: |
edsbas.B3F141D6 |
| Database: |
BASE |