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Time Crystal Behavior of Excited Eigenstates.
Andrzej Syrwid1, Jakub Zakrzewski1,2, Krzysztof Sacha1,2
1Instytut Fizyki imienia Mariana Smoluchowskiego, Uniwersytet Jagielloński, ulica Profesora Stanisława Łojasiewicza 11, PL-30-348 Kraków, Poland.
Physical Review Letters
|January 6, 2018
Summary
Spontaneous breaking of time translation symmetry, crucial for time crystal formation, is achievable in excited states, not ground states. This study simulates this process in ultracold atomic gases.
Area of Science:
- Quantum physics
- Condensed matter physics
- Statistical mechanics
Background:
- Spontaneous breaking of continuous space translation symmetry leads to space crystals.
- A similar mechanism, spontaneous breaking of continuous time translation symmetry, is proposed for time crystal formation.
- Wilczek's original model suggested time crystal formation from the ground state under perturbation, but this is unobservable.
Purpose of the Study:
- To investigate the conditions for observable spontaneous breaking of time translation symmetry.
- To explore the formation of time crystals from excited eigenstates.
- To simulate and analyze the symmetry breaking process and the stability of the resulting time crystal.
Main Methods:
- Theoretical proposal of symmetry breaking in excited eigenstates.
- Experimental realization in ultracold atomic gases.
- Numerical simulations of spontaneous symmetry breaking via particle position measurements.
Main Results:
- Spontaneous breaking of time translation symmetry is observable when starting from an excited eigenstate, not the ground state.
- The process can be simulated by measuring particle positions.
- The lifetime of the resulting symmetry-broken state was analyzed.
Conclusions:
- Time crystals can be formed from excited eigenstates, offering an experimentally viable pathway.
- Measurements play a crucial role in inducing and observing spontaneous time translation symmetry breaking.
- Further research can explore the properties and applications of these experimentally accessible time crystals.
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