On the influence of dilute charged impurity and perpendicular electric field on the electronic phase of phosphorene: Band gap engineering

¹ Institute of Research and Development, Duy Tan University - 03 Quang Trung, Danang, Viet Nam
² Center for Theoretical and Computational Physics, University of Education, Hue University Hue City, Viet Nam
³ Lehrstuhl für Theoretische Physik I, Technische Universität Dortmund - Otto-Hahn Straße 4, 44221 Dortmund, Germany

^(a) thuphuonghueuni@gmail.com
^(b) mohsen.yarmohammadi@tu-dortmund.de

Received: 21 September 2018
Accepted: 17 October 2018

Abstract

Tuning the band gap plays an important role for applicability of 2D materials in the semiconductor industry. The present paper is a theoretical study on the band gap engineering using the electronic density of states (DOS) of phosphorene in the presence of dilute charged impurity and of a perpendicular electric field. The electronic DOS is numerically calculated using a combination of the continuum model Hamiltonian and the Green's function approach. Our findings show that the band gap of phosphorene in the absence and presence of the perpendicular electric field decreases with increasing impurity concentration and/or impurity scattering potential. Further, we found that in the presence of opposite perpendicular electric fields, the electronic DOS of disordered phosphorene shows different changing behaviors stemming from the Stark effect: in the positive case the band gap increases with increasing electric-field strength; whereas in the negative case the band gap disappears. The latter, in turn, leads to the semiconductor-to-semimetal and semiconductor-to-metal phase transition for the case of strong impurity concentrations and strong impurity scattering potentials, respectively. The results can serve as a base for future applications in logic electronic devices.