Correlated band-edge emissions of ZnO nanorods and GaN underlying substrate

Abstract

Vertically aligned ZnO nanorods were grown on GaN substrate with hydrothermal method. Under the excitation of continuous-wave ultraviolet laser, the band-edge emission of the ZnO nanorods exhibits a strong intensity fluctuation with time at low temperatures. More interestingly, it has a distinct correlation with the band-edge emission of the GaN underlying layer. The correlation coefficient is found to be as high as -0.94. The results reveal the presence of random and efficient carrier transfer between the ZnO nanorods and GaN underlying substrate. © 2009 The Japan Society of Applied Physics.