| About this Abstract |
| Meeting |
2011 Electronic Materials Conference
|
| Symposium
|
2011 Electronic Materials Conference
|
| Presentation Title |
U5, Band Edge Optical Transitions in Bulk GaSbN and InAsN Dilute-Nitride Materials |
| Author(s) |
Ding Wang, Stefan Svensson, Leon Shterengas, Gregory Belenky |
| On-Site Speaker (Planned) |
Ding Wang |
| Abstract Scope |
Dilute-nitride GaSbN and InAsN were grown by molecular beam epitaxy on GaSb and InAs substrates, respectively. Photoluminescence (PL) and optical absorption measurements demonstrate strong bandgap reduction with increasing nitrogen incorporation in both materials. GaSbN samples with nitrogen composition ranging up to 1.4% show a redshift of absorption edge by up to 300 meV; while for InAsN, bandgap decreases by approximately 60 meV per atomic percent of nitrogen content. Three times faster bandgap shrinkage in GaSbN indicates stronger interaction between GaSb conduction band edge and nitrogen resonant states. Carrier relaxation lifetimes were studied using an ultra-fast PL up-conversion technique. GaSbN alloys show very short recombination lifetimes in the order of several picoseconds, in accordance with theoretical predictions that GaSbN should have deep nitrogen complex levels in the bandgap. InAsN alloys demonstrate low excitation minority carrier lifetimes of 8 ns for sample with 1% of nitrogen and about 5 ns for sample with 2% of nitrogen at 77 K. Difference in energetic position of nitrogen complex states can be responsible for the observed difference. At room temperature InAsN with 1% nitrogen content still has a minority carrier lifetime of 2.5 ns. More than three orders of magnitude improvement in minority carrier lifetime as compared to GaSbN encourage development of the InAsN as potential material for mid-IR detector applications. |
| Proceedings Inclusion? |
Undecided |