Determination of the Position of a Single Nuclear Spin from Free Nuclear Precessions Detected by a Solid-State Quantum Sensor

TL;DR

This paper introduces a quantum sensing protocol using a nitrogen-vacancy center to determine the azimuthal angle of a single nuclear spin, enabling precise localization at the single-molecule level.

Contribution

The authors develop and experimentally demonstrate a novel protocol combining pulsed DNP, phase-controlled RF pulses, and multipulse AC sensing to determine the azimuthal angle of a nuclear spin.

Findings

Successfully determined the azimuthal angle of a single 13C nuclear spin.

Identified the lattice site of the target nucleus in diamond.

Demonstrated potential for single-molecule magnetic resonance imaging.

Abstract

We report on a nanoscale quantum-sensing protocol which tracks a free precession of a single nuclear spin and is capable of estimating an azimuthal angle---a parameter which standard multipulse protocols cannot determine---of the target nucleus. Our protocol combines pulsed dynamic nuclear polarization, a phase-controlled radiofrequency pulse, and a multipulse AC sensing sequence with a modified readout pulse. Using a single nitrogen-vacancy center as a solid-state quantum sensor, we experimentally demonstrate this protocol on a single 13C nuclear spin in diamond and uniquely determine the lattice site of the target nucleus. Our result paves the way for magnetic resonance imaging at the single-molecular level.