Quantum dynamic response-based NV-diamond magnetometry: Robustness to decoherence and applications in motion detection of magnetic nanoparticles

TL;DR

This paper introduces a quantum sensing protocol using NV centers in diamond to detect magnetic fields and nanoparticle motion via dynamical response, demonstrating robustness to decoherence and advantages over traditional methods.

Contribution

It presents a novel quantum response-based magnetometry method utilizing Berry curvature and quenching protocols, enhancing robustness and capability in motion detection.

Findings

Robustness to decoherence demonstrated through numerical simulations

Ability to detect arbitrary time-dependent magnetic fields in near-adiabatic regimes

Nuclear spin polarization affects sensing performance in a beneficial way

Abstract

We propose a novel quantum sensing protocol that leverages the dynamical response of physical observables to quenches in quantum systems. Specifically, we use the nitrogen-vacancy (NV) color center in diamond to realize both scalar and vector magnetometry via quantum response. Furthermore, we suggest a method for detecting the motion of magnetic nanoparticles, which is challenging with conventional interference-based sensors. To achieve this, we derive the closed exact form of the Berry curvature corresponding to NV centers and design quenching protocols to extract the Berry curvature via dynamical response. By constructing and solving non-linear equations, the magnetic field and instantaneous motion velocity of the magnetic nanoparticle can be deduced. We investigate the feasibility of our sensing scheme in the presence of decoherence and show through numerical simulations that it is robust to decoherence. Intriguingly, we have observed that a vanishing nuclear spin polarization in diamond actually benefits our dynamic sensing scheme, which stands in contrast to conventional Ramsey-based schemes. In comparison to Ramsey-based sensing schemes, our proposed scheme can sense an arbitrary time-dependent magnetic field, as long as its time dependence is nearly adiabatic.