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Entropy production in the nonreciprocal Cahn-Hilliard model.
Thomas Suchanek1, Klaus Kroy1, Sarah A M Loos2
1Institut für Theoretische Physik, Universität Leipzig, Postfach 100 920, D-04009 Leipzig, Germany.
Physical Review. E
|January 20, 2024
Summary
This study explores a nonreciprocal Cahn-Hilliard model, revealing a traveling-wave phase driven by nonreciprocal coupling. Entropy production fluctuations near transitions signal the emergence of this dynamic phase.
Area of Science:
- Statistical Physics
- Non-Hermitian Physics
- Active Matter
Background:
- The nonreciprocal Cahn-Hilliard model serves as a model for non-Hermitian stochastic field theories.
- This model is inherently out of equilibrium due to nonreciprocal coupling, classifying it as an active field theory.
Purpose of the Study:
- To investigate the phases and transitions in the nonreciprocal Cahn-Hilliard model.
- To quantify scale-resolved time-reversal symmetry breaking and entropy production.
- To analyze the dynamics of the emergent traveling-wave phase.
Main Methods:
- Analysis of the nonreciprocal Cahn-Hilliard model with thermal noise.
- Fourier decomposition of the entropy production rate.
- Perturbative calculations in the low-noise regime.
Main Results:
- Identification of homogeneous, static-demixed, and traveling-wave phases.
- The traveling-wave phase is accessible via oscillatory instability or a critical exceptional point.
- Entropy production surges near static-dynamic transitions, driven by long-wavelength fluctuations, heralding the traveling wave.
Conclusions:
- The model exhibits rich phase behavior beyond conventional equilibrium systems.
- Time-reversal symmetry breaking is scale-resolved and depends on nonreciprocal coupling strength.
- The traveling-wave dynamics can be described as the motion of an active quasiparticle.
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