Precursors to Anderson Localization in the Holstein Model: Quantum and Quantum-Classical Solutions

TL;DR

This paper investigates the precursors to Anderson localization in the Holstein model by comparing quantum and quantum-classical solutions, revealing a zero-frequency mobility peak not captured by traditional phenomenological models.

Contribution

It introduces a combined quantum and quantum-classical approach to analyze Holstein polarons, highlighting features missed by previous phenomenological methods.

Findings

Good agreement between quantum and quantum-classical solutions

Identification of a zero-frequency mobility peak

Limitations of phenomenological transient localization approach

Abstract

We calculate the frequency-dependent mobility of the Holstein polaron in one dimension near adiabatic limit using the method based on dynamical quantum tipicality, as well as the quantum-classical method. The agreement between fully quantum and quantum-classical solutions is very good. The most prominent feature is the appearance of a zero-frequency peak in the mobility, in addition to the displaced peak associated to the precursors of Anderson localization. The zero-frequency peak cannot be obtained within the phenomenological transient localization approach, which is often used in a semiquantitative description of charge transport in quasi-one-dimensional organic semiconductors.