Eur. Phys. J. B (2014) 87: 73
https://doi.org/10.1140/epjb/e2014-41010-1

Regular Article

The numerical operator method to the real time dynamics of currents through the nanostructures with different topologies

¹ Institute of Applied Physics, Zhejiang University of Technology, Hangzhou 310023, P.R. China
² Zhejiang Institute of Modern Physics, Department of Physics, Zhejiang University, Hangzhou 310023, P.R. China

^a e-mail: wangpei@zjut.edu.cn

Received: 15 November 2013
Received in final form: 12 February 2014
Published online: 24 March 2014

Abstract

We present the numerical operator method for studying the transient and stationary currents through nanostructures with different topologies, e.g., the flakes of square and honeycomb lattices. We find a quasi-stationary stage in the transient currents through the square flakes, but none in the honeycomb flakes. The stationary current through the square flakes increases smoothly with the voltage bias. In contrast, there is a threshold voltage in the current-voltage curve through a honeycomb flake, indicating a gap at the Fermi energy.