I.
D.
Potirniche
Zhang, J. ., Hess, P. W., Kyprianidis, A. ., Becker, P. ., Lee, A. ., Smith, J. ., … Monroe, C. . (2017). Observation of a discrete time crystal. Nature, 543, 217-+. http://doi.org/10.1038/nature21413