Molecular optomechanics with atomic antennas

TL;DR

This paper demonstrates that a germanium-vacancy defect in diamond acts as an atomic antenna, significantly enhancing Raman scattering efficiency and providing a new approach to surface-enhanced Raman scattering (SERS) with atomic-scale control.

Contribution

The study introduces the use of a germanium-vacancy defect in diamond as an atomic antenna to enhance Raman scattering, offering a novel mechanism distinct from traditional plasmonic SERS.

Findings

Thousand-fold increase in Raman scattering efficiency at low temperatures.

Distinct power dependence of Stokes intensity confirms atomic antenna mechanism.

Efficient excitation mediated by GeV defect with low dissipation.

Abstract

A typical surface-enhanced Raman scattering (SERS) system relies on deeply subwavelength field localization in nanoscale plasmonic cavities to enhance both the excitation and emission of Raman-active molecules. Here, we demonstrate that a germanium-vacancy (GeV) defect in diamond can efficiently mediate the excitation process, by acting as a bright atomic antenna. At low temperatures, the GeV's low dissipation allows it to be efficiently populated by the incident field, resulting in a thousand-fold increase in the efficiency of Raman scattering. We show that atomic antenna-enhanced Raman scattering can be distinguished from conventional SERS by tracing the dependence of Stokes intensity on input power.