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

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 the device at low and high excitation powers. The strong coupling is obtained with a g=16 μeV coupling strength in a 7.3 μm diameter micropillar, with a cavity spectral width κ=20.5 μeV (Q=65 000). The factor of merit of the strong-coupling regime, 4g/κ=3, is the current state-of-the-art for a quantum dot-micropillar system.