Discrete Time Crystals: Rigidity, Criticality, and Realizations
Abstract
Despite being forbidden in equilibrium, spontaneous breaking of time translation symmetry can occur in periodically driven, Floquet systems with discrete timetranslation symmetry. The period of the resulting discrete time crystal is quantized to an integer multiple of the drive period, arising from a combination of collective synchronization and many body localization. Here, we consider a simple model for a onedimensional discrete time crystal which explicitly reveals the rigidity of the emergent oscillations as the drive is varied. We numerically map out its phase diagram and compute the properties of the dynamical phase transition where the time crystal melts into a trivial Floquet insulator. Moreover, we demonstrate that the model can be realized with current experimental technologies and propose a blueprint based upon a one dimensional chain of trapped ions. Using experimental parameters (featuring longrange interactions), we identify the phase boundaries of the iontimecrystal and propose a measurable signature of the symmetry breaking phase transition.
 Publication:

Physical Review Letters
 Pub Date:
 January 2017
 DOI:
 10.1103/PhysRevLett.118.030401
 arXiv:
 arXiv:1608.02589
 Bibcode:
 2017PhRvL.118c0401Y
 Keywords:

 Condensed Matter  Disordered Systems and Neural Networks;
 Condensed Matter  Quantum Gases;
 Condensed Matter  Statistical Mechanics;
 Condensed Matter  Strongly Correlated Electrons;
 Quantum Physics
 EPrint:
 9 pages, 7 figures