Robust quantum sensing with strongly interacting probe systems

TL;DR

This paper demonstrates that strong interactions among quantum probes can significantly improve the robustness and sensitivity of quantum sensing, even at non-zero temperatures, by leveraging long-range interactions.

Contribution

It introduces a novel approach where strong interactions between probe systems enhance robustness and sensitivity in quantum sensing, surpassing traditional non-interacting assumptions.

Findings

Sensitivity can scale exponentially with the number of probes.

Strong interactions increase robustness against thermal noise.

Combining with dynamical decoupling further enhances sensitivity.

Abstract

In the field of quantum metrology and sensing, a collection of quantum systems (e.g. spins) are used as a probe to estimate some physical parameter (e.g. magnetic field). It is usually assumed that there are no interactions between the probe systems. We show that strong interactions between them can increase robustness against thermal noise, leading to enhanced sensitivity. In principle, the sensitivity can scale exponentially in the number of probes -- even at non-zero temperatures -- if there are long-range interactions. This scheme can also be combined with other techniques, such as dynamical decoupling, to give enhanced sensitivity in realistic experiments.