A Green-function approach to transport phenomena in quantum pumps

TL;DR

This paper introduces a Green-function method to analyze transport in quantum systems with time-periodic potentials, focusing on double barrier structures and the factors influencing net current direction.

Contribution

It provides a general Green-function framework for studying transport in tight-binding systems with time-dependent potentials, including analysis of current sign origins.

Findings

Developed a comprehensive Green-function approach for quantum transport.

Analyzed the impact of harmonic potentials on current direction.

Applied method to double barrier structures with different potential configurations.

Abstract

We present a general treatment to study transport phenomena in systems described by tight-binding Hamiltonians coupled to reservoirs and with one or more time-periodic potentials. We apply this treatment to the study of transport phenomena in a double barrier structure with one and two harmonic potentials. Among other properties, we discuss the origin of the sign of the net current.