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. Issue 7 (29th May 2022)

• Record Type: Journal Article
• Authors: Bâldea, Ioan
• Is Part Of: Advanced theory and simulations. Volume 5:Issue 7(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-05-29
• Subjects: charge transport -- conductance -- electron tunneling -- molecular junctions -- thermal effects; Science -- Simulation methods -- Periodicals; Science -- Methodology -- Periodicals; Engineering -- Simulation methods -- Periodicals; Engineering -- Methodology -- Periodicals; 507.21
• DOI: 10.1002/adts.202200158
• Languages: English
• ISSNs: 2513-0390

Abstract

Abstract: It is shown 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, it is shown 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 $1/T$ ‐dependent G at high T (Arrhenius‐like regime). This Sommerfeld–Arrhenius transition can be observed in real molecular junctions and can be continuously tuned, for example, via mechanical stretching. Abstract : The exact formula expressing the conductance of a tunneling junction as a function of temperature T deduced here in closed analytic form in terms of elementary function predicts a thermal transition from a nearly independent T (Sommerfeld) regime to a nearly exponential (Arrhenius) regime that can be continuously tuned, for example, via mechanical stretching or molecular orbital gating.