Type-II GaSb/GaAs coupled quantum rings: Room-temperature luminescence enhancement and recombination lifetime elongation for device applications

Abstract

Type-II GaSb/GaAs coupled quantum rings have exhibited two-order-of-magnitude luminescence enhancement and ten-times elongation of recombination lifetime at room temperature as compared with regular rings. The longer lifetime suggests that a significant amount of electrons are confined in coupled rings rather than simply leaking away. These phenomena indicate that type-II nanostructures can be potentially utilized for room-temperature luminescence and carrier storage applications. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4737443]