Eur. Phys. J. B (2015) 88: 72
https://doi.org/10.1140/epjb/e2015-50549-0

Regular Article

Linear ac transport in square-shaped graphene nanoconstriction devices

¹ School of Science, Jiangnan University, Wuxi 214122, P.R. China
² Zhejiang-California International Nanosystem Institute, Electronic Department, Zhejiang University, Hangzhou 310029, P.R. China
³ Zhejiang Institute of Modern Physics, Department of Physics, Zhejiang University, Hangzhou 310027, P.R. China

^a e-mail: hzzhaoxa@163.com

Received: 14 August 2014
Received in final form: 22 January 2015
Published online: 23 March 2015

Abstract

The linear ac transport of square-shaped graphene nanoconstriction devices are investigated, employing Büttiker’s ac transport theory. Based on Green’s function, the dynamic conductances taking account of both dc and ac contributions are presented. The square-shaped graphene nanoconstriction device displays semiconducting and resonance features in the transporting channels. The device responds capacitively or inductively to the external ac perturbations depending on the dynamic processes of the internal charges at the central nanoconstriction region. We show that as a result of the coupling and the band-mixing between the leads and the central constriction, the ac transport properties are sensitive to the geometry of the graphene systems.