Narrow-linewidth tin-vacancy centers in a diamond waveguide

TL;DR

This paper demonstrates the integration of narrow-linewidth tin-vacancy centers in diamond with nanophotonic waveguides, enabling efficient on-chip quantum photonic applications with stable and high-quality emitters.

Contribution

The authors successfully coupled high-quality SnV$^-$ centers to diamond waveguides using advanced fabrication techniques, achieving narrow linewidths and demonstrating stability under resonant excitation.

Findings

Coupling of SnV$^-$ centers to diamond waveguides confirmed.

Achieved narrow linewidth emission as low as 36 MHz.

Demonstrated stability of waveguide-coupled centers under resonant excitation.

Abstract

Integrating solid-state quantum emitters with photonic circuits is essential for realizing large-scale quantum photonic processors. Negatively charged tin-vacancy (SnV$^-$) centers in diamond have emerged as promising candidates for quantum emitters because of their excellent optical and spin properties including narrow-linewidth emission and long spin coherence times. SnV$^-$ centers need to be incorporated in optical waveguides for efficient on-chip routing of the photons they generate. However, such integration has yet to be realized. In this Letter, we demonstrate the coupling of SnV$^-$ centers to a nanophotonic waveguide. We realize this device by leveraging our recently developed shallow ion implantation and growth method for generation of high-quality SnV$^-$ centers and the advanced quasi-isotropic diamond fabrication technique. We confirm the compatibility and robustness of these techniques through successful coupling of narrow-linewidth SnV$^-$ centers (as narrow as $36\pm2$ MHz) to the diamond waveguide. Furthermore, we investigate the stability of waveguide-coupled SnV$^-$ centers under resonant excitation. Our results are an important step toward SnV$^-$-based on-chip spin-photon interfaces, single-photon nonlinearity, and photon-mediated spin interactions.