Robust optical readout and characterization of nuclear spin transitions in nitrogen-vacancy ensembles in diamond

TL;DR

This paper demonstrates robust optical detection and characterization of nuclear spin transitions in NV centers in diamond, revealing temperature and magnetic field dependencies crucial for quantum sensing.

Contribution

It provides the first detailed analysis of optically detected 14N nuclear spin transitions in diamond NV centers, including temperature and magnetic field effects.

Findings

Nuclear-spin-dependent fluorescence observed with high contrast.

Temperature affects the nuclear quadrupole coupling constant Q.

Magnetic field influences the nuclear spin transition frequencies.

Abstract

Nuclear spin ensembles in diamond are promising candidates for quantum sensing applications, including rotation sensing. Here we perform a characterization of the optically detected nuclear-spin transitions associated with the 14N nuclear spin within diamond nitrogen vacancy (NV) centers. We observe nuclear-spin-dependent fluorescence with the contrast of optically detected 14N nuclear Rabi oscillations comparable to that of the NV electron spin. Using Ramsey spectroscopy, we investigate the temperature and magnetic-field dependence of the nuclear spin transitions in the 77.5-420 K and 350-675 G range, respectively. The nuclear quadrupole coupling constant Q was found to vary with temperature T yielding d|Q|/dT=-35.0(2) Hz/K at T=297 K. The temperature and magnetic field dependencies reported here are important for quantum sensing applications such as rotation sensing and potentially for applications in quantum information processing.