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Quantum Mpemba Effect in a Quantum Dot with Reservoirs.
Amit Kumar Chatterjee1, Satoshi Takada2, Hisao Hayakawa1
1Yukawa Institute for Theoretical Physics, Kyoto University, Kitashirakawa Oiwakecho, Sakyo-ku, Kyoto 606-8502, Japan.
Physical Review Letters
|September 8, 2023
Summary
Researchers observed the quantum Mpemba effect in quantum dots, where initially hotter systems surprisingly cooled faster than colder ones. This thermal quantum Mpemba effect challenges conventional understanding of relaxation dynamics.
Area of Science:
- Quantum physics
- Condensed matter physics
- Statistical mechanics
Background:
- The Mpemba effect describes the counterintuitive phenomenon where hotter water can freeze faster than colder water.
- Understanding anomalous relaxation dynamics is crucial in various physical systems.
Purpose of the Study:
- To demonstrate and investigate the quantum Mpemba effect in a quantum dot system.
- To identify the underlying mechanisms responsible for this anomalous thermal behavior.
Main Methods:
- Utilizing the Anderson model to describe a quantum dot coupled to two reservoirs.
- Analyzing the system's temperature evolution from different initial conditions (hot and cold).
Main Results:
- The study successfully demonstrates the thermal quantum Mpemba effect in the quantum dot system.
- Temperatures of initially hot and cold systems cross at a finite time, reversing their thermal identities.
- The slowest relaxation mode, dominant in Markovian systems, does not drive this quantum Mpemba effect.
Conclusions:
- The quantum Mpemba effect arises from a combination of remaining relaxation modes, not the slowest one.
- Analytical conditions for achieving the quantum Mpemba effect in quantum dot density matrix elements are provided.
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