Nanosecond-scale spectral diffusion in the single photon emission of a GaN quantum dot

Kang Gao,Ivan Solovev,Ivan Solovev,Mark Holmes,Yasuhiko Arakawa,Munetaka Arita

doi:10.1063/1.4997117

Abstract

Autocorrelation measurements are used to reveal the spectral diffusion time scale in the single photon emission of a GaN interface fluctuation quantum dot. Typical characteristic diffusion times of such QDs are revealed to be of nanosecond order. The excitation power dependence of the diffusion rate is also investigated, whereby an increase in the diffusion rate with increasing excitation power is observed. This result provides information on experimental conditions that will be required for the generation of indistinguishable photons.

Highlights

Spectral diffusion is an emission linewidth limiting phenomenon in quantum dots (QDs) involving random jumps in the emission wavelength
As a subset of semiconductor quantum dots, III-Nitride based quantum dots have attracted extensive attention due to their wide emission wavelength range from the ultraviolet to the infrared[18,19,20,21] and their possible high-temperature operation.[22,23,24,25,26]
Fluctuations can occur on timescales varying from sub-nanosecond[30] levels to several seconds,[28] and measuring the fluctuations on fast time scales requires more advanced measurement techniques such as photon autocorrelation.[30]. This converts the spectral fluctuation into an intensity fluctuation and benefits from the sub-nanosecond time resolution of photomultiplier tubes (PMTs) used in a Hanbury Brown & Twiss type setup

Summary

Introduction

Spectral diffusion is an emission linewidth limiting phenomenon in quantum dots (QDs) involving random jumps in the emission wavelength. Nanosecond-scale spectral diffusion in the single photon emission of a GaN quantum dot

Results

Conclusion