Vibron-polaron critical localization in a finite size molecular nanowire

TL;DR

This paper investigates how finite size effects influence vibron-polaron localization in molecular nanowires, revealing size-dependent inhomogeneities and the emergence of high-energy localized states.

Contribution

It introduces a finite size analysis of vibron-polaron dynamics, highlighting the size-dependent dressing mechanism and localization phenomena in nanowires.

Findings

Finite size causes different dressing in side and core molecules.

Core hopping constant depends on nanowire size.

High energy localized states occur below a critical size.

Abstract

The small polaron theory is applied to describe the vibron dynamics in an adsorbed nanowire with a special emphasis onto finite size effects. It is shown that the finite size of the nanowire discriminates between side molecules and core molecules which experience a different dressing mechanism. Moreover, the inhomogeneous behavior of the polaron hopping constant is established and it is shown that the core hopping constant depends on the lattice size. However, the property of a lattice with translational invariance is recovered when the size of the nanowire is greater than a critical value. Finally, it is pointed out that these features yield the occurrence of high energy localized states which both the nature and the number are summarized in a phase diagram in terms of the relevant parameters of the problem (small polaron binding energy, temperature, lattice size).