Phonon-Induced Effects in Quantum Dot Absorption and Resonance Fluorescence with Hierarchy of Pure States

TL;DR

This paper explores how phonon interactions affect the optical properties of quantum dots coupled to a vibrational environment and a leaky cavity, using advanced non-Markovian quantum simulation techniques.

Contribution

It introduces the use of Hierarchy of Pure States to accurately compute multitime correlation functions in a phonon-coupled quantum dot system.

Findings

Phonon coupling broadens absorption and emission lines.

Thermal effects influence the visibility of resonance fluorescence spectra.

Strong phonon coupling significantly alters spectral features.

Abstract

We investigate a quantum dot (QD) system coupled to a vibrational environment with a super-Ohmic spectral density and weakly to a leaky cavity mode, a model relevant for semiconductor-based single-photon sources. The phonon coupling induces dephasing and broadens the absorption and emission line shapes, while the weakly coupled cavity mode leads to effective driving of the QD. To capture non-Markovian effects, we use non-Markovian Quantum State Diffusion and its hierarchical extension the Hierarchy of Pure States to compute multitime correlation functions underlying absorption and resonance fluorescence spectra. We present numerical results for the absorption spectra at strong phonon coupling and finite temperature, as well as for resonance fluorescence spectra at varying phonon coupling strengths and temperatures, and analyse the visibility of the resonance fluorescence spectra to provide insights into how phonon coupling and thermal effects influence the spectral features.