# Observation of a Time Quasicrystal and Its Transition to a Superfluid Time Crystal.

@article{Autti2018ObservationOA, title={Observation of a Time Quasicrystal and Its Transition to a Superfluid Time Crystal.}, author={S. Autti and V. B. Eltsov and Grigory E. Volovik}, journal={Physical review letters}, year={2018}, volume={120 21}, pages={ 215301 } }

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 ^{3}He-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…

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