Broadband microwave detection using electron spins in a hybrid diamond-magnet sensor chip

TL;DR

This paper demonstrates a broadband microwave detection method using a hybrid diamond-magnet sensor chip, enabling high-fidelity spin control over gigahertz bandwidths for advanced quantum sensing applications.

Contribution

It introduces a novel hybrid sensor chip that converts microwave signals to the sensor's frequency via non-linear spin-wave dynamics, broadening detection bandwidths significantly.

Findings

Achieved gigahertz-range microwave detection with high fidelity.

Enabled characterization of spin-wave bands at multiple gigahertz.

Demonstrated potential for spin-based sensing in the 100 GHz regime.

Abstract

Quantum sensing has developed into a main branch of quantum science and technology. It aims at measuring physical quantities with high resolution, sensitivity, and dynamic range. Electron spins in diamond are powerful magnetic field sensors, but their sensitivity in the microwave regime is limited to a narrow band around their resonance frequency. Here, we realize broadband microwave detection using spins in diamond interfaced with a thin-film magnet. A pump field locally converts target microwave signals to the sensor-spin frequency via the non-linear spin-wave dynamics of the magnet. Two complementary conversion protocols enable sensing and high-fidelity spin control over a gigahertz bandwidth, allowing characterization of the spin-wave band at multiple gigahertz above the sensor-spin frequency. The pump-tunable, hybrid diamond-magnet sensor chip opens the way for spin-based sensing in the 100-gigahertz regime at small magnetic bias fields.