Manipulation of resonant tunneling by substrate-induced inhomogeneous energy band gaps in graphene with square superlattice potentials

• Published in: Physics letters. A 2013-11, Vol.377 (40), p.2895-2900
• Main Authors: Li, Guanqiang, Chen, Guangde, Peng, Ping, Cao, Zhenzhou, Ye, Honggang
• Format: Article
• Language: English
• Subjects: Bandgaps induced by substrate; Energy bands; Graphene; Resonant tunneling; Superlattice with square potential
• ISSN: 0375-9601; 1873-2429
• DOI: 10.1016/j.physleta.2013.08.038

We investigate the resonant transmission of Dirac electrons through inhomogeneous band gap graphene with square superlattice potentials by transfer matrix method. The effects of the incident angle of the electrons, Fermi energy and substrate-induced Dirac gaps on the transmission are considered. It is found that the Dirac gap of graphene adds another degree of freedom with respect to the incident angle, the Fermi energy and the parameters of periodic superlattice potentials (i.e., the number, width and height of the barriers) for the transmission. In particular, the inhomogeneous Dirac gap induced by staggered substrates can be used to manipulate the transmission. The properties of the conductance and Fano factor at the resonant peaks are found to be affected by the gaps significantly. The results may be helpful for the practical application of graphene-based electronic devices.