Observation of a Time Quasicrystal and Its Transition to a Superfluid Time Crystal
Research output: Contribution to journal › Article › Scientific › peer-review
|Journal||Physical Review Letters|
|Publication status||Published - 25 May 2018|
|MoE publication type||A1 Journal article-refereed|
- Lancaster University
- Landau Institute for Theoretical Physics
We report experimental realization of a quantum time quasicrystal and its transformation to a quantum time crystal. We study Bose-Einstein condensation of magnons, associated with coherent spin precession, created in a flexible trap in superfluid He3-B. Under a periodic drive with an oscillating magnetic field, the coherent spin precession is stabilized at a frequency smaller than that of the drive, demonstrating spontaneous breaking of discrete time translation symmetry. The induced precession frequency is incommensurate with the drive, and hence, the obtained state is a time quasicrystal. When the drive is turned off, the self-sustained coherent precession lives a macroscopically long time, now representing a time crystal with broken symmetry with respect to continuous time translations. Additionally, the magnon condensate manifests spin superfluidity, justifying calling the obtained state a time supersolid or a time supercrystal.