Time crystals in doped semiconductors

Spin ensembles in semiconductors provide a unique experimental platform for the observation of emergent many-body dynamics like many-body localization and quantum chaos. High precision quantum control of electron and nuclear spins in phosphorus doped silicon have been utilized to uncover the many-body correlations in decoherence. We present here the experimental observation of a many-body time crystal, a novel dynamical phase of matter with spontaneously broken time translation symmetry, in periodically driven nanoscale electron spins in phosphorus doped silicon. The signatures of time crystalline correlations were studied as a function of spin concentration. These observations can be theoretically captured by the paradigmatic central spin model previously used for describing decoherence in this system.