Issue
EPL
Volume 88, Number 1, October 2009
Article Number 17008
Number of page(s) 5
Section Condensed Matter: Electronic Structure, Electrical, Magnetic and Optical Properties
DOI http://dx.doi.org/10.1209/0295-5075/88/17008
Published online 27 October 2009
EPL, 88 (2009) 17008
DOI: 10.1209/0295-5075/88/17008

A time-dependent momentum-space density functional theoretical approach for electron transport dynamics in molecular devices

Zhongyuan Zhou and Shih-I Chu

Department of Chemistry, University of Kansas - Lawrence, KS 66045, USA

zyzhov@ku.edu

received 18 April 2009; accepted in final form 24 September 2009; published October 2009
published online 27 October 2009

Abstract
We propose a time-dependent density functional theoretical (TDDFT) approach in momentum $(\mathcal{P})$ space for the study of electron transport in molecular devices under arbitrary biases. The basic equation of motion, which is a time-dependent integrodifferential equation obtained by Fourier transform of the time-dependent Kohn-Sham equation in spatial coordinate $(\mathcal{R})$ space, is formally exact and includes all the effects and information of the electron transport in the molecular devices. The electron wave function is calculated by solving this equation in a finite $\mathcal{P} $-space volume. This approach is free of self-energy function and memory term related to the electrodes in the $\mathcal{R} $ space and beyond the wide-band limit (WBL). The feasibility and power of the approach are demonstrated by the calculation of current through one-dimensional systems.

PACS
73.63.-b - Electronic transport in nanoscale materials and structures.
85.65.+h - Molecular electronic devices.
71.15.Pd - Molecular dynamics calculations (Carr-Parrinello) and other numerical simulations.

© EPLA 2009