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Updated: Nov 21, 2025
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Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
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Slow Nonthermalizing Dynamics in a Quantum Spin Glass
Louk Rademaker1, Dmitry A Abanin1
1Department of Theoretical Physics, University of Geneva, 1211 Geneva, Switzerland.
Physical Review Letters
|January 15, 2021
Summary
This study explores quantum dynamics in 1D spin glasses, revealing distinct behaviors at high and low energy densities. At low energies, spin glass order persists due to inefficient resonance avalanches, unlike many-body localization (MBL).
Area of Science:
- Condensed matter physics
- Quantum dynamics
- Disordered quantum systems
Background:
- Spin glasses and many-body localization (MBL) are key examples of ergodicity breaking.
- Their origins differ: rugged classical energy landscapes for spin glasses and quantum interference for MBL.
- Understanding ergodicity breaking in quantum systems is crucial for quantum technologies.
Purpose of the Study:
- Investigate the quantum dynamics of an isolated 1D spin glass under a transverse field.
- Characterize the system's behavior at different energy densities.
- Explore the physical mechanisms behind ergodicity breaking and potential distinctions from MBL.
Main Methods:
- Numerical studies of quantum dynamics.
- Resonance analysis to probe system behavior.
- Application of a transverse field to a 1D spin glass model.
Main Results:
- At high energy densities, the system is ergodic, relaxing via a resonance avalanche mechanism.
- This avalanche mechanism also destroys MBL in non-glassy systems with power-law interactions.
- At low energy densities, a power-law soft gap in interaction-induced fields hinders the resonance avalanche.
- This leads to the persistence of spin-glass order.
- A small fraction of resonant spins forms a distinct thermalizing system with long-range entanglement.
Conclusions:
- The 1D spin glass model exhibits distinct dynamical regimes based on energy density.
- The persistence of spin-glass order at low energies is driven by an inefficient resonance avalanche mechanism.
- This system, realizable in trapped ions, offers a platform for studying slow quantum dynamics and glassiness.
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