Spin-Acoustic Control of Silicon Vacancies in 4H Silicon Carbide

TL;DR

This paper demonstrates acoustically mediated spin control of silicon vacancies in 4H-Silicon Carbide using a high-Q resonator, enabling room-temperature coherent control and stress mapping, with implications for quantum memory and device characterization.

Contribution

It introduces a novel method of spin control via acoustic resonance in silicon carbide, combining optically detected magnetic resonance with high-Q acoustic resonators.

Findings

Achieved near linewidth spin transition narrowing using acoustic drive.

Demonstrated room-temperature coherent population oscillations.

Mapped stress distribution inside a bulk acoustic wave resonator.

Abstract

We demonstrate direct, acoustically mediated spin control of naturally occurring negatively charged silicon monovacancies (V$_{Si}^-$) in a high quality factor Lateral Overtone Bulk Acoustic Resonator fabricated out of high purity semi-insulating 4H-Silicon Carbide. We compare the frequency response of silicon monovacancies to a radio-frequency magnetic drive via optically-detected magnetic resonance and the resonator's own radio-frequency acoustic drive via optically-detected spin acoustic resonance and observe a narrowing of the spin transition to nearly the linewidth of the driving acoustic resonance. We show that acoustic driving can be used at room temperature to induce coherent population oscillations. Spin acoustic resonance is then leveraged to perform stress metrology of the lateral overtone bulk acoustic resonator, showing for the first time the stress distribution inside a bulk acoustic wave resonator. Our work can be applied to the characterization of high quality-factor micro-electro-mechanical systems and has the potential to be extended to a mechanically addressable quantum memory.