Many-body treatment of quantum transport through single molecules

TL;DR

This paper introduces a many-body theoretical framework for quantum transport in single molecules, accurately capturing excited states and matching experimental thermopower and conductance data, revealing complex many-body effects.

Contribution

It presents a semi-empirical many-body Hamiltonian approach that accounts for all molecular states, enabling detailed analysis of transport properties without free parameters.

Findings

Reproduces experimental thermopower and conductance values

Reveals many-body effects in molecular transport

Shows the 'molecular diamond' structure in transport data

Abstract

We develop a theoretical approach to quantum transport through single conjugated organic molecules that accurately accounts for all molecular excited and ground states via a semi-empirical many-body molecular Hamiltonian. We then calculate the linear and non-linear transport properties of a benzenedithiol molecule covalently bonded to two gold electrodes at room temperature, eliminating all free parameters by comparing the calculated thermopower and linear-conductance with experiment. The resulting `molecular diamond' structure exhibits experimentally observed many-body effects inaccessible to mean-field approaches.