Programme

O.21 -- Oral, VCTP-44

Date: Thursday, 1 August 2019

Time: 16:30 - 16:50

Tight binding description for the electronic band structure of penta-graphene

Vu Thanh Tra (1), Nguyen Thi Kim Quyen (2), Tran Van Truong (3)

(1) Department of Physics, School of Education, Can Tho University, Can Tho, Vietnam (2) Faculty of Engineering and Technology, Kien Giang University, Kien Giang, Vietnam (3) SRMP, CEA Saclay, Université Paris-Saclay, F-91191, Gif-sur-Yvette, France

Penta-graphene, a new carbon allotrope discovered recently has attracted great attention from researchers due to its high potentials as a large bandgap semiconductor, which is an intriguing feature for many applications in nanoelectronics. Understanding of the electronic properties of this materials is therefore necessary to modulate its properties. In this work, we present an effective tight-binding (TB) model which can induce the energy bands that being consistent with results from ab initio calculations. Besides the comparison of our simple TB model to previous ones, we also supplemented further neighbor interactions into the TB Hamiltonian to analyze the band structure and considered the impact of each type of TB parameters such as onsite and hopping energies, overlap terms of wave functions on the shape of the energy bands. Then a set of appropriate parameters was selected to reproduce reasonably important characters in the band structure captured by ab initio calculations. Further analysis was also carried out to examine the density of states by using Green’s function. Moreover, we also investigated the impact of a vertical electric field on the electronic properties of penta-graphene and showing a strong modulation of the bandgap in the presence of such external field.

Presenter: Nguyen Thi Kim Quyen