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Stochastic Discrete Time Crystals: Entropy Production and Subharmonic Synchronization.
Lukas Oberreiter1, Udo Seifert1, Andre C Barato2
1II. Institut für Theoretische Physik, Universität Stuttgart, 70550 Stuttgart, Germany.
Physical Review Letters
|January 29, 2021
Summary
Discrete time crystals exhibit broken time translation symmetry through subharmonic oscillations. This study introduces a thermodynamic model, revealing coherent oscillations emerge in 2D models even without synchronization.
Area of Science:
- Condensed matter physics
- Quantum thermodynamics
Background:
- Discrete time crystals (DTCs) are driven quantum systems exhibiting broken time-translation symmetry.
- Subharmonic oscillations are a hallmark of DTCs, indicating spontaneous symmetry breaking.
- Stochastic thermodynamics provides a framework to analyze energy dissipation in non-equilibrium systems.
Purpose of the Study:
- To introduce a thermodynamically consistent model for discrete time crystals.
- To analyze the energy dissipation in a many-body system of interacting noisy subharmonic oscillators.
- To investigate the emergence of collective phenomena like synchronization and time-crystalline phases.
Main Methods:
- Development of a thermodynamically consistent model for discrete time crystals.
- Analysis using the framework of stochastic thermodynamics.
- Evaluation of energy dissipation rates in interacting noisy subharmonic oscillators.
Main Results:
- The mean-field model exhibits subharmonic synchronization, characterized by collective oscillations.
- The 2D model demonstrates a time-crystalline phase without synchronization.
- Coherent subharmonic oscillations emerge in the 2D model, showing power-law scaling with system size.
Conclusions:
- Emergence of coherent oscillations in discrete time crystals is possible without synchronization.
- The thermodynamic model provides insights into the non-equilibrium dynamics of DTCs.
- The study highlights distinct behaviors in mean-field versus 2D discrete time crystal models.
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