Single-spin magnetometry with multi-pulse sensing sequences

TL;DR

This paper demonstrates enhanced single-spin magnetometry using multi-pulse sequences, optimizing sensing time and phase/frequency filtering to improve magnetic field detection sensitivity.

Contribution

It introduces experimentally validated multi-pulse sensing sequences that optimize measurement sensitivity by balancing decoherence effects and sensing duration.

Findings

Multi-pulse sequences significantly improve sensing sensitivity.

Optimal number of sensing cycles balances decoherence and sensing time.

Full frequency-filtering characteristics of multi-pulse schemes are characterized.

Abstract

We experimentally demonstrate single-spin magnetometry with multi-pulse sensing sequences. The use of multi-pulse sequences can greatly increase the sensing time per measurement shot, resulting in enhanced ac magnetic field sensitivity. We theoretically derive and experimentally verify the optimal number of sensing cycles, for which the effects of decoherence and increased sensing time are balanced. We perform these experiments for oscillating magnetic fields with fixed phase as well as for fields with random phase. Finally, by varying the phase and frequency of the ac magnetic field, we measure the full frequency-filtering characteristics of different multi-pulse schemes and discuss their use in magnetometry applications.