Quantum dot-cavity strong-coupling regime measured through coherent reflection spectroscopy in a very high-Q micropillar

TL;DR

This paper demonstrates strong light-matter coupling in a high-Q micropillar with a single quantum dot, using coherent reflection spectroscopy to measure and analyze the system's optical properties at various excitation powers.

Contribution

It reports the first measurement of strong coupling in a high-Q micropillar with a quantum dot, achieving a record factor of merit 4g/kappa=3.

Findings

Achieved strong coupling with g=16 μeV in a 7.3 μm micropillar

Measured cavity spectral width κ=20.5 μeV, Q=65,000

Demonstrated state-of-the-art strong-coupling factor of 4g/κ=3

Abstract

We report on the coherent reflection spectroscopy of a high-quality factor micropillar, in the strong coupling regime with a single InGaAs annealed quantum dot. The absolute reflectivity measurement is used to study the characteristics of our device at low and high excitation power. The strong coupling is obtained with a g=16 \mueV coupling strength in a 7.3\mum diameter micropillar, with a cavity spectral width kappa=20.5 \mueV (Q=65 000). The factor of merit of the strong-coupling regime, 4g/kappa=3, is the current state-of-the-art for a quantum dot-micropillar system.