Non-resonant dot-cavity coupling and its applications in resonant quantum dot spectroscopy

TL;DR

This paper investigates non-resonant coupling between a quantum dot and a micro-cavity, demonstrating its potential for quantum optics applications by observing photon anti-bunching and enabling detailed quantum dot property measurements.

Contribution

It provides the first experimental evidence of non-resonant dot-cavity coupling with applications in quantum dot spectroscopy and quantum information technology.

Findings

Strong photon anti-bunching observed in emission signals

Detection of Stokes and anti-Stokes-like emissions at large detunings

Non-resonant coupling enables monitoring of quantum dot properties

Abstract

We present experimental investigations on the non-resonant dot-cavity coupling of a single quantum dot inside a micro-pillar where the dot has been resonantly excited in the s-shell, thereby avoiding the generation of additional charges in the QD and its surrounding. As a direct proof of the pure single dot-cavity system, strong photon anti-bunching is consistently observed in the autocorrelation functions of the QD and the mode emission, as well as in the cross-correlation function between the dot and mode signals. Strong Stokes and anti-Stokes-like emission is observed for energetic QD-mode detunings of up to ~100 times the QD linewidth. Furthermore, we demonstrate that non-resonant dot-cavity coupling can be utilized to directly monitor and study relevant QD s-shell properties like fine-structure splittings, emission saturation and power broadening, as well as photon statistics with negligible background contributions. Our results open a new perspective on the understanding and implementation of dot-cavity systems for single-photon sources, single and multiple quantum dot lasers, semiconductor cavity quantum electrodynamics, and their implementation, e.g. in quantum information technology.