Conductance through analytic constrictions

TL;DR

This paper investigates how the shape of nanocontacts affects their conductance, revealing resonance effects especially in spherical geometries, using analytic models and the recursion-transfer-matrix method.

Contribution

It introduces an analytic approach to study conductance dependence on nanocontact shape, highlighting resonance phenomena in spherical contacts.

Findings

Conductance varies significantly with contact shape.

Resonance effects are prominent in spherical contacts.

Shape sensitivity impacts nanocontact electronic properties.

Abstract

We study the dependence of the intrinsic conductance of a nanocontact on its shape by using the recursion-transfer-matrix method. Hour-glass, torus, and spherical shapes are defined through analytic potentials, the latter two serving as rough models for ring-like and spherical molecules, respectively. The sensitivity of the conductance to geometric details is analyzed and discussed. Strong resonance effects are found for a spherical contact weakly coupled to electron reservoirs.