Long-distance excitation of nitrogen-vacancy centers in diamond via surface spin waves

TL;DR

This paper demonstrates long-distance excitation of nitrogen-vacancy centers in diamond using surface spin waves, enabling coherent communication over millimeter scales at room temperature, which could enhance quantum information processing.

Contribution

It introduces a method to mediate NV center interactions via surface spin waves over millimeter distances at room temperature, a novel approach for quantum communication.

Findings

Surface spin waves can mediate NV center excitation over distances exceeding 3 mm.

MSSW amplitude increases linearly with microwave power, indicating potential for signal amplification.

Room-temperature MSSWs are robust and suitable for scalable quantum information applications.

Abstract

Coherent communication over mesoscale distances is a necessary condition for the application of solid-state spin qubits to scalable quantum information processing. Among other routes under study, one possibility entails the generation of magnetostatic surface spin waves (MSSW) dipolarly coupled to shallow paramagnetic defects in wide-bandgap semiconductors. As an initial step in this direction, here we make use of room-temperature MSSWs to mediate the interaction between the microwave field from an antenna and the spin of a nitrogen-vacancy (NV) center in diamond. We show that this transport spans distances exceeding 3 mm, a manifestation of the MSSW robustness and long diffusion length. Using the NV spin as a local sensor, we find that the MSSW amplitude grows linearly with the applied microwave power, suggesting this approach could be extended to amplify the signal from neighboring spin qubits by several orders of magnitude.