• Corpus ID: 237386584

A comment on"Discrete time crystals: rigidity, criticality, and realizations"

@inproceedings{Khemani2021ACO,
  title={A comment on"Discrete time crystals: rigidity, criticality, and realizations"},
  author={Vedika Khemani and Roderich Moessner and S. L. Sondhi},
  year={2021}
}

• V. Khemani, R. Moessner, S. Sondhi
• Published 1 September 2021
• Physics

The Letter by N. Y. Yao et. al. [1, 2] presents three models for realizing a many-body localized discrete time-crystal (MBL DTC): a short-ranged model [1], its revised version [2], as well as a long-range model of a trapped ion experiment [1, 3]. We show that none of these realize an MBL DTC for the parameter ranges quoted in Refs. [1, 2]. The central phase diagrams in [1] therefore cannot be reproduced. The models show rapid decay of oscillations from generic initial states, in sharp contrast to the robust period doubling dynamics characteristic of an MBL DTC. Long-lived oscillations from special initial states (such as polarized states) can be understood from the familiar low-temperature physics of a static transverse field Ising model, rather than the nonequilibrium physics of an eigenstate-ordered MBL DTC. Our results on the long-range model also demonstrate, by extension, the absence of an MBL DTC in the trapped ion experiment of Ref. [3].