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Quantum Time Crystals from Hamiltonians with Long-Range Interactions
Valerii K Kozin1,2, Oleksandr Kyriienko3,4,5
1Science Institute, University of Iceland, Dunhagi 3, IS-107 Reykjavik, Iceland.
Physical Review Letters
|December 7, 2019
Summary
Researchers demonstrate a new Hamiltonian for closed quantum systems, enabling genuine time crystals by breaking continuous time-translational symmetry (TTS). This breakthrough challenges previous impossibility theorems and reveals connections between discrete and continuous TTS.
Area of Science:
- Quantum physics
- Condensed matter physics
Background:
- Time crystals break time-translational symmetry (TTS).
- Floquet time crystals are known in open quantum systems with discrete TTS.
- Genuine time crystals in closed quantum systems were thought impossible.
Purpose of the Study:
- To propose a Hamiltonian for unitary time crystal behavior in closed quantum systems.
- To break continuous time-translational symmetry (TTS).
- To investigate the stability and properties of these novel time crystals.
Main Methods:
- Utilizing a spin-1/2 many-body Hamiltonian with long-range multispin interactions (spin strings).
- Analyzing unitary dynamics to observe time crystalline behavior.
- Perturbation analysis at zero temperature to assess stability.
Main Results:
- Demonstrated a Hamiltonian that exhibits time crystalline behavior in closed quantum systems.
- Achieved breaking of continuous time-translational symmetry (TTS).
- Confirmed stability of quantum time crystals against local perturbations at zero temperature.
Conclusions:
- Proved the possibility of genuine time crystals in closed quantum systems.
- Established a link between continuous and discrete time-translational symmetry (TTS).
- Opened new avenues for exploring quantum matter phases.
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