Defence Research Agency

About: Defence Research Agency is a based out in . It is known for research contribution in the topics: Synthetic aperture radar & Radar. The organization has 1211 authors who have published 1109 publications receiving 31542 citations.

Auger recombination dynamics of InxGa1-xSb

Abstract: The alloy In1-xGaxSb has been identified as potentially an important component in mid-infrared laser diodes which use band structure engineering of quantum structures based on the narrow-gap III-V material InSb. A pump-probe measurement has been made of carrier recombination in bulk In1-xGaxSb, for a range of alloy compositions. Over the range of excited carrier densities (5 × 1016-3 × 1017 cm-3) and at the temperatures (30-300 K) studied experimentally, contributions to the recombination from Auger, Shockley-Read-Hall and radiative mechanisms were calculated using an analytic approximation, with carrier degeneracy included. Excellent agreement with experiment was obtained over the alloy range x = 0.0-0.2 (corresponding to a room-temperature energy gap variation from 0.175 eV to 0.215 eV). Numerically the room-temperature Auger coefficient, C, decreased from the value 1.17 × 1026 cm6 s-1 at x = 0 (i.e. InSb) to 0.98 × 1026 cm6 s-1 at x = 0.2. The fact that C decreases with energy gap increase, in good agreement with theoretical predictions, is important for strained layer quantum well device applications.

Rapidly Deployable Network System for Critical Communications in Remote Locations

Abstract: This paper presents a transportable and rapidly deployable network system, which can be used to provide local voice, video and data connectivity for critical communications in remote locations and Internet connectivity through commercial mobile network, if available. The network is a stand-alone system, which is independent of external electricity and Internet. It is built with commercial off-the-shelf equipment and software. This paper presents trials of a local tactical voice service, a TETRA-compatible push to talk application, and Licensed Shared Access evolution spectrum manager along with radio signal measurements on 700 MHz and 2300 MHz frequency bands.