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Non-Markovian Mpemba effect in mean-field systems.
1School of Physics, Southeast University, Nanjing 211189, China.
Physical Review. E
|June 25, 2020
Summary
The Mpemba effect (ME), where hotter substances freeze faster, is observed in mean-field systems. This study reveals ME arises from non-Markovian relaxation dynamics, offering new theoretical insights.
Area of Science:
- Statistical Physics
- Condensed Matter Physics
Background:
- The Mpemba effect (ME) describes the counterintuitive phenomenon where initially hotter systems freeze faster than cooler ones.
- Understanding the underlying mechanisms of ME is crucial for various scientific disciplines.
Purpose of the Study:
- To investigate the existence and mechanisms of the Mpemba effect in mean-field systems (MFS).
- To establish a theoretical framework for non-Markovian ME.
Main Methods:
- Utilized the microcanonical Monte Carlo algorithm to simulate thermal contact between MFS and a thermal reservoir.
- Analyzed the paramagnetic-ferromagnetic phase transition dynamics.
Main Results:
- Demonstrated the Mpemba effect in mean-field systems, with hotter systems transitioning faster.
- Identified non-Markovian back-reaction of the MFS on the reservoir as the origin of ME.
- Confirmed ME persists in the thermodynamic limit and is influenced by reservoir size.
Conclusions:
- Established a theoretical non-Markovian framework for the Mpemba effect.
- The findings may contribute to a broader understanding of ME mechanisms in diverse systems, including water.
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