Integer Quantum Hall Effect in a Two-Orbital Square Lattice with Chern Number C = 2Supported by the Natural Science Foundation of Jiangsu Province under Grant No BK20140450, the Huaian Science and Technology (Industry) Project under Grant Nos HAG2014043 and HAG2014019, and the Youth Foundation of Huaiyin Normal University under Grant No 13HSQNZ03

• Published in: Chinese physics letters 2016-11, Vol.33 (11)
• Main Authors: Yu, Hua-Ling, Zhai, Zhang-Yin, Bian, Xin-Tian
• Format: Article
• Language: English
• ISSN: 0256-307X; 1741-3540
• DOI: 10.1088/0256-307X/33/11/117305

We investigate numerically the integer quantum Hall effect in a two-orbital square lattice. The Hall plateau σH = 2(e2/h) is well defined with the Chern number C = ±2. With the increasing disorder, both the Hall plateau and the gap of density of states decrease gradually in width, and finally the gap disappears before vanishing of the Hall plateau. Compared with the Hall plateau induced by the external magnetic field, the one in our system is more robust against disorder. We also find that the transition from the Hall plateau to zero Hall conductance becomes sharper by increasing the size of the system.