Growth of sparse arrays of narrow GaN nanorods hosting spectrally stable InGaN quantum disks

Abstract

Wafer-scale production of single InGaN quantum disks (QD) in-a-nanorod array with small rod diameter (> 9 nm) and low rod-density (< 10(8) cm(-2)) has been achieved without extensive processing steps. Excitation power-dependent mu PL spectrum of single QD reveals multi-excitonic peak with 0.75 meV blue-shift for 3 orders of magnitude increasing power, indicating the present system is spectrally stable and nearly free of quantum-confined Stark effects, due possibly to the strain relaxation induced by free surface of small rod diameters. The fully polarized emissions, a high working temperature (180 K), low rod density and good alignment, render this system promising as a potential quantum photon source. (C) 2012 Optical Society of America