Efficient readout of a single spin state in diamond via spin-to-charge conversion

TL;DR

This paper introduces a room-temperature method for efficiently reading out the spin state of NV centers in diamond by converting spin information into charge states, enabling near-quantum-limited sensitivity for quantum sensing.

Contribution

The authors develop a novel spin-to-charge conversion technique for NV centers that significantly improves readout efficiency at room temperature.

Findings

Spin readout noise is within a factor of three of the spin projection noise.

The method enables single-shot charge state readout of NV centers.

Potential applications in nanoscale magnetic sensing are discussed.

Abstract

Efficient readout of individual electronic spins associated with atom-like impurities in the solid state is essential for applications in quantum information processing and quantum metrology. We demonstrate a new method for efficient spin readout of nitrogen-vacancy (NV) centers in diamond. The method is based on conversion of the electronic spin state of the NV to a charge state distribution, followed by single-shot readout of the charge state. Conversion is achieved through a spin-dependent photoionization process in diamond at room temperature. Using NVs in nanofabricated diamond beams, we demonstrate that the resulting spin readout noise is within a factor of three of the spin projection noise level. Applications of this technique for nanoscale magnetic sensing are discussed.