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Published on: December 4, 2017
General quantum Brownian motion with initially correlated and nonlinearly coupled environment
1School of Physical Sciences, Jawaharlal Nehru University, New Delhi 110 067, India.
Summary
This study analyzes quantum Brownian motion in open systems with nonlinear coupling and initial correlations. We derived the influence functional and propagator, showing the system obeys the fluctuation-dissipation theorem.
Area of Science:
- Quantum mechanics
- Statistical physics
Background:
- Open quantum systems exhibit complex dynamics influenced by their environment.
- Quantum Brownian motion describes a quantum system interacting with a bath.
- Nonlinear coupling and initial correlations significantly alter system dynamics.
Purpose of the Study:
- To analyze the dynamics of an open quantum system undergoing quantum Brownian motion.
- To investigate the effects of nonlinear system-environment coupling and initial correlations.
- To derive and apply the influence functional and propagator for specific potentials.
Main Methods:
- Perturbative approach up to second order in the coupling constant.
- Explicit evaluation of the propagator for harmonic and washboard potentials.
- Derivation of master and Wigner equations for correlated initial conditions.
Main Results:
- The influence functional was obtained perturbatively for nonlinear couplings.
- The propagator was explicitly evaluated for harmonic and washboard potentials.
- Master and Wigner equations were derived, and the fluctuation-dissipation theorem was confirmed.
Conclusions:
- The study provides a detailed analysis of quantum Brownian motion under nonlinear coupling and initial correlations.
- The derived propagator and equations offer insights into the system's behavior.
- The system's adherence to the fluctuation-dissipation theorem was demonstrated.
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