Exact analytic formula for conductance predicting a tunable Sommerfeld-Arrhenius thermal transition within a single-step tunneling mechanism in molecular junctions subject to mechanical stretching

• Published in: arXiv.org
• Main Author: Baldea, Ioan
• Format: Paper Journal Article
• Language: English
• Published: Ithaca Cornell University Library, arXiv.org 22.10.2022
• Subjects: Charge transport; Diimide; Energy levels; Physics - Chemical Physics; Physics - Materials Science; Physics - Mesoscale and Nanoscale Physics; Stretching; Tunnel junctions
• ISSN: 2331-8422
• DOI: 10.48550/arxiv.2210.12544

We show that the conductance \(G\) of molecular tunnel junctions wherein the charge transport is dominated by a single energy level can be expressed in closed analytic form which is exact and valid at arbitrary temperature \(T\) and model parameter values. On this basis, we show that the single-step tunneling mechanism is compatible with a continuous thermal transition from a weakly \(T\)-dependent \(G\) at low \(T\) (Sommerfeld regime) to a nearly exponential \(1/T\)-dependent \(G\) at high \(T\) (Arrhenius-like regime). We predict that this Sommerfeld-Arrhenius transition can be observed in real molecular junctions % (e.g., based on perylene diimide) and can be continuously tuned, e.g., via mechanical stretching.