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Disordering a permutation symmetric system: Revivals, thermalization, and chaos
Manju C1, Uma Divakaran1, Arul Lakshminarayan2
1Indian Institute of Technology Palakkad, Department of Physics, Palakkad, Kerala 678623, India.
Physical Review. E
|November 18, 2025
Summary
Introducing disorder to quantum systems breaks symmetry, forcing quantum states into larger Hilbert spaces. This study shows disorder can drive systems chaotic but also reveals surprising robustness in quantum revivals.
Area of Science:
- Quantum mechanics
- Quantum chaos
- Many-body physics
Background:
- Symmetry plays a crucial role in quantum system dynamics.
- Disorder can fundamentally alter quantum state evolution.
- The quantum kicked top is a paradigmatic model for studying quantum chaos.
Purpose of the Study:
- To investigate the impact of symmetry-breaking disorder on quantum system dynamics.
- To analyze the transition from integrable to chaotic regimes under disorder.
- To quantify the robustness of quantum phenomena like revivals to disorder.
Main Methods:
- Utilizing the quantum kicked top model for N qubits.
- Employing linear entropy to measure single-qubit entanglement.
- Analyzing spectral statistics to characterize system phases.
- Comparing quantum calculations with classical approximations.
Main Results:
- Disorder forces quantum states out of symmetric subspaces into larger Hilbert spaces.
- Increasing disorder drives the system towards a chaotic phase.
- Quantum revivals exhibit robustness against disorder, dependent on system chaos.
- Classical calculations accurately predict quantum entanglement in the disorder-free limit.
Conclusions:
- Symmetry-breaking disorder significantly impacts quantum dynamics, leading to chaos.
- The quantum kicked top demonstrates resilience to disorder, particularly in its chaotic regime.
- Entanglement dynamics provide key insights into disorder-induced transitions.
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