# AC Josephson effect between two superfluid time crystals

@article{Autti2020ACJE, title={AC Josephson effect between two superfluid time crystals}, author={S. Autti and Pekka Heikkinen and Jere T. M{\"a}kinen and Grigory E. Volovik and V V Zavjalov and V. B. Eltsov}, journal={Nature Materials}, year={2020}, pages={1-4} }

Quantum time crystals are systems characterized by spontaneously emerging periodic order in the time domain 1 . While originally a phase of broken time translation symmetry was a mere speculation 2 , a wide range of time crystals has been reported 3 – 5 . However, the dynamics and interactions between such systems have not been investigated experimentally. Here we study two adjacent quantum time crystals realized by two magnon condensates in superfluid 3 He-B. We observe an exchange of magnons…

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