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Stalled response near thermal equilibrium in periodically driven systems
Lennart Dabelow1,2, Peter Reimann3
1RIKEN Center for Emergent Matter Science (CEMS), Wako, Saitama, 351-0198, Japan.
Nature Communications
|January 4, 2024
Summary
Time-periodic perturbations cause stalled response in isolated quantum systems. Driving effects diminish significantly as systems approach thermal equilibrium, suppressing reactions.
Area of Science:
- Condensed Matter Physics
- Quantum Many-Body Systems
- Statistical Mechanics
Background:
- Understanding system responses to external perturbations is fundamental in physics.
- Linear response theory is often insufficient for complex systems with many degrees of freedom or those far from equilibrium.
Purpose of the Study:
- To investigate the response of isolated many-body quantum systems to time-periodic perturbations.
- To analyze the phenomenon of 'stalled response' in systems thermalizing or near thermal equilibrium.
Main Methods:
- Analysis of isolated many-body quantum systems under time-periodic driving.
- Consideration of systems starting far from equilibrium and those near equilibrium.
- Complementary numerical simulations, analytical descriptions, and qualitative arguments.
Main Results:
- A phenomenon termed 'stalled response' is observed under moderate-strength periodic perturbations.
- Driving effects are significantly suppressed as the system approaches thermal equilibrium.
- Systems initially near thermal equilibrium exhibit minimal response to perturbations.
Conclusions:
- The response of isolated quantum systems to periodic driving is strongly dependent on their proximity to thermal equilibrium.
- Stalled response highlights a suppression of dynamic reactions in systems nearing equilibrium, challenging conventional response predictions.
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