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An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
Published on: December 4, 2017
External-noise-driven bath and the generalized semiclassical Kramers theory
Pradipta Ghosh1, Anindita Shit, Sudip Chattopadhyay
1Department of Chemistry, Bengal Engineering and Science University, Shibpur, Howrah 711103, India.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|January 15, 2011
Summary
This study investigates quantum effects on the decay rate of metastable states in Brownian particles subjected to a correlated noise-driven bath. Numerical analysis reveals how these quantum effects influence the system
Area of Science:
- Quantum thermodynamics
- Statistical mechanics
- Condensed matter physics
Background:
- Systems are often open, exchanging energy and matter with their environment.
- Externally driving a heat bath can create unique thermodynamic conditions.
- Understanding decay from metastable states is crucial in various physical scenarios.
Purpose of the Study:
- To investigate quantum effects on the decay rate of a metastable Brownian particle.
- To analyze systems where the heat bath is externally driven, creating an open thermodynamic system.
- To develop a theoretical framework for correlated noise-driven baths.
Main Methods:
- Derivation of the operator-valued Langevin equation from a system-reservoir model.
- Development of the c-number analog incorporating leading-order quantum effects.
- Formulation and solution of the quantum Fokker-Planck equation.
- Thorough numerical analysis of the derived rate expression.
Main Results:
- The quantum Fokker-Planck equation successfully models the system's dynamics.
- Quantum effects significantly influence the rate of decay from the metastable state.
- The derived rate expression provides a quantitative measure of these quantum influences.
Conclusions:
- The study provides a robust theoretical framework for analyzing open quantum systems with driven baths.
- Quantum effects are essential for accurately predicting decay rates in such systems.
- The findings offer insights into physical situations involving metastable states and correlated noise.
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