Floquet time-crystals as sensors of AC fields

TL;DR

This paper explores how Floquet time-crystals can serve as highly sensitive quantum sensors for weak AC fields, leveraging their unique long-range order and robustness to noise to surpass classical limits.

Contribution

It demonstrates that Floquet time-crystals can outperform traditional sensors by overcoming shot noise limits and maintaining stability through collective interactions.

Findings

Time-crystals can surpass shot noise limit in sensing

Long interrogation times enhance sensitivity

Collective interactions stabilize dynamics against noise

Abstract

The long range spatial and temporal ordering displayed by discrete time crystals, can become advantageous properties when used for sensing extremely weak signals. Here, we investigate their performance as quantum sensors of weak AC-fields and demonstrate, using the quantum Fisher information measure, that they can overcome the shot noise limit while allowing long interrogation times. In such systems, collective interactions stabilize their dynamics against noise making them robust enough to protocol imperfections.