Complex absorbing potential based Lorentzian fitting scheme and time dependent quantum transport

TL;DR

This paper introduces a CAP-based Lorentzian expansion method to efficiently model quantum transport, applicable to both tight-binding and first-principles systems, demonstrated on graphene nanoribbons and benzene molecules.

Contribution

It develops a novel Lorentzian expansion scheme based on CAP to improve the efficiency of quantum transport simulations in diverse models.

Findings

Effective simulation of transient currents in graphene nanoribbons.

Successful application to benzene molecular junctions.

Enhanced computational efficiency over traditional methods.

Abstract

Based on the complex absorbing potential (CAP) method, a Lorentzian expansion scheme is developed to express the self-energy. The CAP-based Lorentzian expansion of self-energy is employed to solve efficiently the Liouville-von Neumann equation of one-electron density matrix. The resulting method is applicable for both tight-binding and first-principles models, and is used to simulate the transient currents through graphene nanoribbons and a benzene molecule sandwiched between two carbon-atom-chains.