The long-range spatial and temporal ordering exhibited by time crystals can become advantageous when used to detect extremely weak signals. Here we investigate their performance as quantum sensors for AC fields and demonstrate, using the quantum Fisher information measure, that they can surpass the limit of non-interacting particles while allowing for long detection times. In these systems, collective interactions stabilize their dynamics against noise, making the sensor robust enough to imperfections in the measurement protocol.

*references: https://arxiv.org/abs/2306.03927, https://doi.org/10.48550/arXiv.2406.06273