Coupling nitrogen vacancy centers in silicon carbide to nanophotonic resonators

TL;DR

This paper demonstrates that nanophotonic resonators in silicon carbide significantly enhance photon collection and magnetic sensing capabilities of nitrogen vacancy centers, advancing scalable quantum technology applications.

Contribution

It introduces scalable micro-resonator structures in silicon carbide that improve photon extraction and spin-readout of nitrogen vacancy centers, enabling better quantum sensing.

Findings

4-fold increase in photon collection

2.4-fold reduction in spectral noise

24% improvement in magnetic field sensitivity

Abstract

Silicon carbide (SiC) is a promising platform for scalable quantum technologies owing to its well-established, wafer-scale industrial processing. SiC also hosts a variety of optically active color centres including the nitrogen vacancy defect that has a spin-triplet ground state. However, strong phonon coupling in the infrared range limits photon extraction from these defects. Here, we use nanophotonic structures, specifically micro-pillar and micro-disk resonators, to enhance optical collection and spin-readout. The micro-pillar geometry yields a 4-fold increase in photon collection, accompanied by a 2.4-fold reduction in spectral noise in optically detected magnetic resonance measurements. Consequently, the magnetic field sensitivity is improved by 24%. The large mode volume of the micro-disk supports resonances spanning 1150-1250 nm, enabling broadband coupling to nitrogen vacancy emission lines. Our results demonstrate that fabrication of scalable photonic structures efficiently improves performance of silicon carbide color centers for integrated quantum light generation and sensing.