Investigation of the spectral triplet in strongly coupled quantum dot-nanocavity system

TL;DR

This paper experimentally studies the power-dependent spectral behavior of a strongly coupled quantum dot-nanocavity system, revealing unexpected spectral features at higher excitation powers that differ from traditional atomic cavity QED predictions.

Contribution

It provides new insights into the excitation power effects and pumping processes in semiconductor quantum dot-cavity systems, expanding understanding beyond conventional atomic cavity QED models.

Findings

Vacuum Rabi doublet observed at low power

Emergence of a third emission peak at higher power

Spectral changes attributed to unique pumping processes

Abstract

We experimentally investigated the excitation power dependence of a strongly coupled quantum dot (QD)-photonic crystal nanocavity system by photoluminescence (PL) measurements. At a low-excitation power regime, we observed vacuum Rabi doublet emission at QD-cavity resonance condition. With increasing excitation power, in addition to the doublet, a third emission peak appeared. This observed spectral change is unexpected from conventional atomic cavity quantum electrodynamics. The observations can be attributed to featured pumping processes in the semiconductor QD-cavity system.