A unified approach to electron transport in double barrier structures

TL;DR

This paper presents a unified theoretical framework for electron transport in double barrier structures that encompasses both sequential and resonant tunneling across various regimes, clarifying concepts and incorporating scattering effects.

Contribution

It introduces a comprehensive approach that unifies different tunneling models and clarifies the concept of transport regimes in double barrier structures.

Findings

Unified model covers coherent to incoherent regimes

Effective mean free path accounts for scattering in the well

Density of states formula relates to tunneling probabilities

Abstract

In this paper we show an approach to electron transport in double barrier structures which unifies the well known sequential and resonant tunneling models in the widest range of transport regimes, from completely coherent to completely incoherent. In doing so, we make a clear distinction between ``approaches'' and ``transport regimes,'' in order to clarify some ambiguities in the concept of sequential tunneling. Scattering processes in the well are accounted for by means of an effective mean free path, which plays the role of a relaxation length. Our approach is based on a recently derived formula for the density of states in a quantum well, as a function of the round trip time in the well and of trasmission and reflection probabilities for the whole structure and for each barrier.