Programme

O.4 -- Oral, NCTP-43

Date: Monday, 30 July 2018

Time: 11:30 - 11:50

Dependence of hopping parameters in penta - graphene's structure by using Tight binding calculations method

Nguyen Thi Kim Quyen (1), Pham Thi Nhu Y (2), Tran Van Truong (3), Vu Thanh Tra (4)

(1) Faculty of Engineering and Technology, Kien Giang University, Kien Giang, Vietnam; (2) School of Graduate, College of Natural Sciences, Can Tho University, Can Tho, Vietnam; (3) EM2C, CentraleSupelec, Universite Paris Saclay, CNRS, 92295 Chatenay Malabry, France; (4) Department of Physics, School of Education, Can Tho University, Can Tho, Vietnam

In 2014, a new carbon allotrope discovered by Wang Qian and her coworker – is called penta – graphene. Similar to graphene, penta - graphene is a single lattice of carbon atoms, but atoms in this structure are more different than ones in graphene. To be specific, penta - graphene’s structure adds more sp3- hybridized carbon atoms; it is important to destroy the symmetry at Fermi level and open the energy gap in band structure. This property is a convenient condition for applications in nanoelectronics. Consequently, penta - graphene has got great attention from researchers. In this paper, we use tight – binding calculations to investigate the energy band - dependent hopping elements. Besides comparing our model with previous Tight binding models, we also supplemented more interaction between next nearest neighbors to analyze the band structure through the effect of hopping parameters. Then choosing the apposite parameters to make the band more properly and clearly. Moreover, the necessary elements to present electronic energy are pointed out, such as overlap factor and onsite energy of carbon atoms. Thereafter, to more indicate the arrangement of the electrons, we continued to calculate the density of states by using Green’s function formalism. Alternatively, based on graphene’s experience, we propose an approach by using the vertical electric field to control the gap of penta - graphene as well as applying it for the electronic devices.

Presenter: Nguyen Thi Kim Quyen