Nuclear spin pair coherence in diamond for atomic scale magnetometry

TL;DR

This paper demonstrates how analyzing electron spin coherence oscillations in diamond can reveal detailed information about nuclear spin clusters, enabling advanced quantum sensing and potential quantum computing applications.

Contribution

It introduces a method to decode electron spin coherence to identify properties of nuclear spin clusters in diamond, enhancing quantum sensing and qubit control.

Findings

Strong coupling nuclear spin clusters cause millisecond oscillations.

Analysis of oscillations reveals positions, orientations, and coupling strengths.

Nuclear spins in diamond can serve as qubits and high-resolution sensors.

Abstract

The nitrogen-vacancy (NV) centre, as a promising candidate solid state system of quantum information processing, its electron spin coherence is influenced by the magnetic field fluctuations due to the local environment. In pure diamonds, the environment consists of hundreds of C-13 nuclear spins randomly spreading in several nanometers range forming a spin bath. Controlling and prolonging the electron spin coherence under the influence of spin bath are challenging tasks for the quantum information processing. On the other hand, for a given bath distribution, many of its characters are encoded in the electron spin coherence. So it is natural to ask the question: is it possible to 'decode' the electron spin coherence, and extract the information about the bath structures? Here we show that, among hundreds of C-13 bath spins, there exist strong coupling clusters, which give rise to the millisecond oscillations of the electron spin coherence. By analyzing these oscillation features, the key properties of the coherent nuclear spin clusters, such as positions, orientations, and coupling strengths, could be uniquely identified. This addressability of the few-nuclear-spin cluster extends the feasibility of using the nuclear spins in diamond as qubits in quantum computing. Furthermore, it provides a novel prototype of single-electron spin based, high-resolution and ultra-sensitive detector for the chemical and biological applications.