# Observation of a Space-Time Crystal in a Superfluid Quantum Gas.

@article{Smits2018ObservationOA, title={Observation of a Space-Time Crystal in a Superfluid Quantum Gas.}, author={J. Smits and Lei Liao and Henk T. C. Stoof and P. van der Straten}, journal={Physical review letters}, year={2018}, volume={121 18}, pages={ 185301 } }

Time crystals are a phase of matter, for which the discrete time symmetry of the driving Hamiltonian is spontaneously broken. The breaking of discrete time symmetry has been observed in several experiments in driven spin systems. Here, we show the observation of a space-time crystal using ultracold atoms, where the periodic structure in both space and time is directly visible in the experimental images. The underlying physics in our superfluid can be described ab initio and allows for a clear…

## 64 Citations

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