Hybrid Integration of GaP Photonic Crystal Cavities with Silicon-Vacancy Centers in Diamond by Stamp-Transfer

TL;DR

This paper presents a novel stamp-transfer fabrication method for integrating GaP photonic crystal cavities with silicon-vacancy centers in diamond, enhancing photon-defect interactions for quantum networks without damaging the diamond host.

Contribution

It introduces a stamp-transfer technique for integrating GaP cavities with SiV centers in diamond, avoiding diamond etching and enabling cavity tuning and high-quality factors.

Findings

Achieved cavity quality factors up to 8900.

Observed a three-fold lifetime reduction indicating strong coupling.

Potential for high cooperativity in quantum network applications.

Abstract

Optically addressable solid-state defects are emerging as one of the most promising qubit platforms for quantum networks. Maximizing photon-defect interaction by nanophotonic cavity coupling is key to network efficiency. We demonstrate fabrication of gallium phosphide 1-D photonic crystal waveguide cavities on a silicon oxide carrier and subsequent integration with implanted silicon-vacancy (SiV) centers in diamond using a stamp-transfer technique. The stamping process avoids diamond etching and allows fine-tuning of the cavities prior to integration. After transfer to diamond, we measure cavity quality factors ($Q$) of up to 8900 and perform resonant excitation of single SiV centers coupled to these cavities. For a cavity with $Q$ of 4100, we observe a three-fold lifetime reduction on-resonance, corresponding to a maximum potential cooperativity of $C = 2$. These results indicate promise for high photon-defect interaction in a platform which avoids fabrication of the quantum defect host crystal.