Quantum entanglement distribution using a magnetic field sensor

TL;DR

This paper proposes using a magnetic field sensor based on NV centers in nanodiamond to entangle remote electronic spins, enabling robust quantum entanglement distribution with potential for practical implementation.

Contribution

It introduces a novel method of entangling distant qubits via a mobile NV-center-based sensor acting as a flying qubit and performing local measurements.

Findings

Device is robust against dephasing and vibrations.

Feasibility of a demonstrator experiment with a fixed sensor.

Potential for quantum computing applications.

Abstract

Sensors based on crystal defects, especially nitrogen vacancy (NV) centres in nanodiamond, can achieve detection of single magnetic moments. Here we show that this exquisite control can be utilized to entangle remote electronic spins for applications in quantum computing; the mobile sensor provides a `flying' qubit while the act of sensing the local field constitutes a two-qubit projective measurement. Thus the tip mediates entanglement between an array of well-separated (and thus well controlled) qubits. Our calculations establish that such a device would be remarkably robust against realistic issues such as dephasing and multimodal vibrations in the sensor tip. We also provide calculations establishing the feasibility of performing a demonstrator experiment with a fixed sensor in the immediate future.