All-optical coherent population trapping with defect spin ensembles in silicon carbide

TL;DR

This paper demonstrates all-optical control of spin states in divacancy defects in silicon carbide, revealing their spin structure and enabling coherent population trapping for quantum applications.

Contribution

It provides the first detailed magneto-spectroscopy analysis of divacancy spins in SiC and demonstrates all-optical coherent population trapping in these ensembles.

Findings

Identified the S=1 spin structure of divacancy defects.

Demonstrated all-optical coherent population trapping.

Revealed decay pathways via intersystem crossing.

Abstract

Divacancy defects in silicon carbide have long-lived electronic spin states and sharp optical transitions, with properties that are similar to the nitrogen-vacancy defect in diamond. We report experiments on 4H-SiC that investigate all-optical addressing of spin states with the zero-phonon-line transitions. Our magneto-spectroscopy results identify the spin $S=1$ structure of the ground and excited state, and a role for decay via intersystem crossing. We use these results for demonstrating coherent population trapping of spin states with divacancy ensembles that have particular orientations in the SiC crystal.