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Quantum Mpemba Effect from Non-Normal Dynamics
1Dipartimento di Fisica, Politecnico di Milano, Piazza L. da Vinci 32, I-20133 Milano, Italy.
Entropy (Basel, Switzerland)
|June 26, 2025
Summary
Researchers discovered a new quantum Mpemba effect mechanism in memoryless quantum systems. Non-orthogonal Liouvillian eigenmodes cause anomalous early-time relaxation, distinct from prior explanations.
Area of Science:
- Quantum physics
- Quantum thermodynamics
Background:
- The quantum Mpemba effect describes faster relaxation from a farther non-equilibrium state.
- Existing explanations involve strong Mpemba effects, non-Markovian memory, and system-reservoir entanglement.
Purpose of the Study:
- To identify a new mechanism for the quantum Mpemba effect in Markovian quantum dynamics.
- To explain anomalous relaxation via the non-normal nature of the Liouvillian superoperator.
Main Methods:
- Theoretical analysis of Liouvillian superoperator non-normality.
- Modeling quantum emitter-waveguide interactions in a waveguide quantum electrodynamics system.
Main Results:
- Non-orthogonal Liouvillian eigenmodes lead to transient interference, causing anomalous early-time relaxation.
- This mechanism, distinct from strong Mpemba effects, can result in slower relaxation for states closer to equilibrium.
- Demonstrated in a waveguide quantum electrodynamics model where couplings induce non-normality.
Conclusions:
- A novel, universal source of Mpemba-like behavior in memoryless quantum systems is revealed.
- Expands the theoretical understanding of anomalous relaxation in quantum systems.
- Suggests new control possibilities in engineered quantum platforms.
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