Quantum Effects in a Mechanically Modulated Single Photon Emitter

TL;DR

This paper proposes a scheme for coupling quantum emitters in h-BN membranes to their mechanical motion, enabling strong interactions, vibrational cooling, and frequency comb generation for advanced quantum and spectroscopic applications.

Contribution

It introduces a novel dispersive coupling mechanism between embedded quantum emitters and membrane vibrations, demonstrating strong coupling and potential for high-precision spectroscopy.

Findings

Strong coupling regime achieved between membrane vibrations and electronic states.

Numerical confirmation of efficient vibrational ground-state cooling.

Emission spectrum exhibits a frequency comb with small spacings.

Abstract

Recent observation of quantum emitters in monolayers of hexagonal boron nitride (h-BN) has provided a novel platform for optomechanical experiments where the single-photon emitters can couple to the motion of freely suspended h-BN membrane. Here, we propose a scheme where the electronic degree of freedom of an embedded color center is coupled to the motion of the hosting h-BN resonator via dispersive forces. We show that the coupling of membrane vibrations to the electronic degree of freedom of the emitter can reach the strong regime. By suitable driving of a three-level $\Lambda$-system composed of two spin degrees of freedom in the electronic ground state as well as an isolated excited state of the emitter a multiple electromagnetically induced transparency spectrum becomes available. The experimental feasibility of the efficient vibrational ground-state cooling of the membrane via quantum interference effects in the two-color drive scheme is numerically confirmed. More interestingly, the emission spectrum of the defect exhibits a frequency comb with frequency spacings as small as the fundamental vibrational mode, which finds applications in high-precision spectroscopy.