Influence of typical environments on quantum processes

TL;DR

This paper investigates how different environmental conditions affect quantum coherence in a simplified model of electronic tunneling, providing a unified framework to understand decoherence mechanisms.

Contribution

It introduces a unified approach using Schwinger's formalism to analyze environmental effects on quantum coherence in a resonant tunneling model.

Findings

Environmental states influence quantum coherence differently.

Derived expressions for transmission coefficients under various conditions.

Unified description of decoherence mechanisms in quantum tunneling.

Abstract

We present the results of studying the influence of different environmental states on the coherence of quantum processes. We choose to discuss a simple model which describe two electronic reservoirs connected through tunneling via a resonant state. The model could, e.g., serve as an idealization of inelastic resonant tunneling through a double barrier structure. We develop Schwinger's closed time path formulation of non-equilibrium quantum statistical mechanics, and show that the influence of the environment on a coherent quantum process can be described by the value of a generating functional at a specific force value, thereby allowing for a unified discussion of destruction of phase coherence by various environmental states: thermal state, classical noise, time dependent classical field, and a coherent state. The model allows an extensive discussion of the influence of dissipation on the coherent quantum process, and expressions for the transmission coefficient are obtained in the possible limits.