Supervisor: A/Prof. Lan Wang
Topological insulators are novel quantum materials discovered in recent years [1-6]. The material system has a bulk insulating state and a conducting edge state which has fascinating characteristics. Both three dimensional (3D) and two dimensional (2D) topological insulators have been experimentally realized. Two dimensional (2D) topological insulators are insulating in their interior, but support one-dimensional (1D) conducting modes on their boundaries. These edge modes are protected from backscattering hence can carry currents for macroscopic distances with very low resistance. Furthermore, if the 2D topological insulator can be magnetized, a true zero resistance edge transport can be realized. This is quantum anomalous Hall effect. Realizing high temperature quantum anomalous Hall effect will generate a revolution in modern electronics industry.
This project will involve in making ferromagnet/2D topological insulator heterostructures based on atomic layer thick 2D materials, fabricating various quantum devices based on these heterostructure, and performing electron and spin transport measurements on these devices. The key idea is to use 2D ferromagnetic insulator to magnetize 2D topological insulator by proximity effect. As 2D materials are amenable to manipulation by electrostatic gates (the basis of conventional field-effect transistors), transport measurements with electric field gating will be the most important measurements in this project. Students with strong physics background are preferred.
The aim of this project will be fabricate the next generation low energy electronic devices, such as topological field effect transistors and topological logic devices.
References:
[1] M. Z. Hasan and C. L. Kane, Rev. Mod. Phys. 82, 3045 (2010) [2] X. L. Qi and S. C. Zhang, Rev. Mod. Phys. 83, 1057 (2011) [3] D. Pesin and A. H. MacDonald, Nature Mater. 11, 409 (2012) [4] A. A. Taskin, Z. Ren, S. Sasaki, K. Segawa, and Y. Ando, Phy. Rev. Lett. 107, 016801 (2011) [5] B. Xia, P. Ren, A. Sulaev, P. Liu, S.Q. Shen, and L. Wang, Physical Review B 87, 085442 (2013) [6] Y. Xu, I. M. Miotkowski, C. Liu, J. Tian, H. Nam, N. Alidoust, J. Hu, C. K. Shih, M. Z. Hasan, and Y. P. Chen, Nature Phys. 10, 956 (2014)Contact Details:
To discuss this project further contact: Associate Professor Lan Wang (lan.wang@rmit.edu.au) 1st Supervisor – Office building 14, Level 6, room 14