All-optical Tuning of Indistinguishable Single-Photons Generated in Three-level Quantum Systems

TL;DR

This paper presents a new all-optical spectral tuning method for quantum dot single-photon sources using a three-level system, enabling fast control and potential quantum information applications.

Contribution

It introduces a novel coherent driving scheme for three-level quantum systems, combining Autler-Townes and ac Stark effects, with experimental validation for spectral tuning of single-photon emitters.

Findings

Feasibility of all-optical spectral tuning demonstrated experimentally.

Achieved fast optical control of quantum emitter spectrum.

Potential for spectral shaping and high-dimensional quantum state generation.

Abstract

Resonance fluorescence of two-level quantum systems has emerged as a powerful tool in quantum information processing. Extension of this approach to higher-level systems provides new opportunities for quantum optics applications. Here we introduce a coherent driving scheme of a three-level ladder system utilizing Autler-Townes and ac Stark effects by resonant excitation with two laser fields. We propose theoretically and demonstrate experimentally the feasibility of this approach towards all-optical spectral tuning of quantum dot-based single-photon sources and investigate photon indistinguishability and purity levels. Our tuning technique allows for fast optical control of the quantum emitter spectrum which paves the way towards temporal and spectral shaping of the single photons, formation of topological Floquet states or generation of high-dimensional frequency-encoded quantum states of light.