Experimental Proposal on Scalable Radio-Frequency Magnetometer with Trapped Ions

TL;DR

This paper proposes a scalable trapped-ion magnetometer using mixed dynamical decoupling, achieving ultra-sensitive radio-frequency magnetic field detection with robustness to noise and inhomogeneity, demonstrated through numerical simulations.

Contribution

It introduces a novel mixed dynamical decoupling method for scalable trapped-ion magnetometry, enhancing sensitivity and robustness over existing techniques.

Findings

Achieves 13 fT/√Hz sensitivity in simulations.

Demonstrates robustness to magnetic field drift and inhomogeneity.

Extends coherence time to several minutes.

Abstract

Quantum magnetometry represents a fundamental component of quantum metrology, where trapped-ion systems have achieved $\rm{pT}/\sqrt{\rm{Hz}}$ sensitivity in single-ion radio-frequency magnetic field measurements via dressed states based dynamical decoupling. Here we propose a scalable trapped-ion magnetometer utilizing the mixed dynamical decoupling method, combining dressed states with periodic sequences to suppress decoherence and spatial magnetic field inhomogeneity. With numerical simulations for a $10^4$ ion system with realistic experimental parameters, we demonstrate that a sensitivity of 13 $\rm{fT}/\sqrt{\rm{Hz}}$ for the radio-frequency field could be reached. Such a sensitivity could be obtained via robust resilience to magnetic field drift noise and inhomogeneity, where coherence time could be extended to the order of several minutes on average. This method enables scalable trapped-ion magnetometry, demonstrating its potential as a robust and practical solution for advancing quantum sensing applications.