High-performance Sources of Multidimensionally Engineered Quantum Light Based on Monolithic Microcavity-metalens Interfaces

TL;DR

This paper introduces integrated microcavity-metalens devices that generate high-quality, multidimensionally engineered quantum light, enabling advanced quantum photonic applications with enhanced control over photon properties.

Contribution

It presents a novel monolithic integration of quantum-dot micropillar sources with ultra-thin metalenses, achieving high-brightness, indistinguishable single photons with multi-degree-of-freedom control.

Findings

High-purity, bright, and indistinguishable single-photon emission achieved.

Simultaneous control of emission divergence, directionality, polarization, and OAM.

Generation of polarization-OAM entanglement and stable quantum skyrmions.

Abstract

The ultimate non-classic light sources for modern photonic quantum technology require on-demand generation of indistinguishable quantum light with high brightness and flexible engineering of quantum emission in multiple degrees of freedom. In this work, we present monolithic microcavity-metalens interfaces consisting of quantum-dot-micropillar single-photon sources and ultra-thin metalenses accurately aligned on opposite sides of an III-V compound semiconductor chip. The pronounced cavity quantum electrodynamics effect enabled by the micropillar cavity facilitates single-photon emission from quantum dots with simultaneous high degrees of single-photon purity, source brightness and photon indistinguishability while the multi-functional metalenses concurrently tailor quantum emission in multiple physical degrees of freedom including radiation divergence, emission directionality, polarization state and orbital angular momentum (OAM). Furthermore, high-fidelity polarization-OAM entanglement and single photons with local spin topologies are successfully generated in our integrated device. In particular, we demonstrate stable propagations of single-photon skrymions in atmospheric turbulence and reveal their topological advantages over the conventional structured quantum light. Our work advances the research fields of integrated quantum photonics and meta-optics, providing integrated high-dimensional quantum light sources for advanced photonic quantum science and technology.