The transition mechanisms of type-II GaSb/GaAs quantum-dot infrared light-emitting diodes

Abstract

The light-emitting diode (LED) with a single GaSb QD layer embedded in a GaAs n-i-p structure operated under different injection currents and temperatures is investigated. With increase in injection currents, room-temperature electroluminescence (EL) peak blue shift is observed until a saturation of EL intensity is reached. In the temperature-varying EL measurements, with increase in temperatures. EL peak blue shift and then red shift are observed, which is attributed to the enhanced luminescence of the smaller QDs with increase in temperatures lower than 100 K. The understanding of the operation mechanisms for the device is advantageous for the practical application of type-II LEDs. (C) 2010 Elsevier B.V. All rights reserved.