Anti-Stokes excitation of solid-state quantum emitters for nanoscale thermometry

TL;DR

This paper demonstrates efficient Anti-Stokes excitation of quantum emitters in solids, enabling a highly sensitive all-optical nanoscale thermometry technique that surpasses existing methods.

Contribution

It introduces a novel Anti-Stokes excitation approach for quantum emitters, enabling practical nanoscale thermometry with improved sensitivity and potential for fundamental studies.

Findings

Efficient Anti-Stokes excitation of germanium-vacancy centers in diamond.

Development of a temperature-dependent, phonon-assisted thermometry scheme.

Outperforms existing optical nanoscale thermometry methods.

Abstract

Color centers in solids are the fundamental constituents of a plethora of applications such as lasers, light emitting diodes and sensors, as well as the foundation of advanced quantum information and communication technologies. Their photoluminescence properties are usually studied under Stokes excitation, in which the emitted photons are at a lower energy than the excitation ones. In this work, we explore the opposite Anti-Stokes process, where excitation is performed with lower energy photons. We report that the process is sufficiently efficient to excite even a single quantum system, namely the germanium-vacancy center in diamond. Consequently, we leverage the temperature-dependent, phonon-assisted mechanism to realize an all-optical nanoscale thermometry scheme that outperforms any homologous optical method employed to date. Our results frame a promising approach for exploring fundamental light-matter interactions in isolated quantum systems, and harness it towards the realization of practical nanoscale thermometry and sensing.