Quantum correlation in disordered spin systems: entanglement and applications to magnetic sensing

TL;DR

This paper presents a method to generate and protect entangled states in disordered spin systems, enhancing magnetic sensing capabilities with solid-state spins like Nitrogen-Vacancy centers.

Contribution

It introduces a coherent control strategy to create GHZ-like and spin-squeezed states in randomly placed spins, improving robustness against decoherence.

Findings

Successful generation of entangled states in disordered spin ensembles

Enhanced magnetic sensitivity in nanoscale magnetometry

Protection of entanglement against decoherence

Abstract

We propose a strategy to generate a many-body entangled state in a collection of randomly placed, dipolarly coupled electronic spins in the solid state. By using coherent control to restrict the evolution into a suitable collective subspace, this method enables the preparation of GHZ-like and spin-squeezed states even for randomly positioned spins, while in addition protecting the entangled states against decoherence. We consider the application of this squeezing method to improve the sensitivity of nanoscale magnetometer based on Nitrogen-Vacancy spin qubits in diamond.