III-Nitride high temperature single-photon sources

Abstract

Nitride based GaN and InGaN quantum dots are excellent single-photon emitters at high temperature owing to their wide bandgap and large exciton binding energy [1-5]. In this work, two different molecular beam epitaxy (MBE) grown nanostructures have been investigated for single-photon emission: InGaN/GaN disk-in-nanowire and InGaN/GaN self-organized quantum dot. Single-photon emission under both optical and electrical excitation has been observed from a single InGaN quantum contained in a GaN nanowire p-n junction. We demonstrate electrically driven single-photon emission, with a g (2) (0) = 0.35, from a single InGaN quantum dot emitting in the green spectral range (λ=520 nm) up to 125 K. Additionally, a self-organized InGaN/GaN single quantum dot diode was grown and fabricated. Emission from a single quantum dot (λ=620 nm) shows single-photon emission with g (2) (0) = 0.29 at room temperature. On-demand single-photon emission by electrical pumping of the quantum dot at an excitation repetition rate of 200 MHz was demonstrated.