Saturated blue-violet electroluminescence from single ZnO microanowire and p-GaN film hybrid light-emitting diodes

摘要

Saturated electroluminescence behavior was observed in single ZnO microanowire and GaN film heterojunctions fabricated by transferring an individual ZnO microanowire onto p-type GaN substrate. A strong blue emission of ～460?nm was observed, as a result of interfacial radiative recombination of electrons from n-ZnO and holes from p-GaN. Light-output-current characteristic followed a power law of L?～?Im, which revealed a superlinear dependence at low current (m?=?1.16) and became sublinear (m?=?0.72) at high current. According to theoretical analysis, the saturated electroluminescence at high current could be attributed to the saturation of nonradiative recombination and the limitation of electrical-to-optical conversion efficiency.