Program

O.9 -- Oral, NCTP-41

Date: Monday, 1 August 2016

Time: 16h00 - 16h20

Magnetic and topological transitions in an insulator with doped magnetic impurities

Hong-Son Nguyen (1), Duc-Anh Le (2), and Minh-Tien Tran (3,4)

(1) Department of Occupational Safety and Health, Trade Union University, 169 Tay Son, Hanoi, Vietnam (2) Faculty of Physics, Hanoi National University of Education,136 Xuan Thuy, Cau Giay, Hanoi, Vietnam (3) Institute of Research and Development, Duy Tan University, K7/25 Quang Trung, Danang, Vietnam (4) Institute of Physics, Vietnam Academy of Science and Technology, 10 Dao Tan, Hanoi, Vietnam

Magnetic and topological transitions in an insulator doped with magnetic impurities is studied based on an interplay between the spin-orbit coupling of electrons and the spin exchange of these electrons with magnetic impurity moments. The model is constructed based on the Kane-Mele model in the presence of magnetic impurities. The magnetic and topological transitions are detected by monitoring the topological invariant and the spontaneous magnetization, which are self consistently determined within the dynamical mean-field theory. We find different magnetic topological phase transitions, depending on the electron filling. At half filling an antiferromagnetic topological insulator, which exhibits the quantum spin Hall effect, exists in the phase region between the paramagnetic topological insulator and the trivially topological antiferromagnetic insulator. At quarter and three quarters fillings, a ferromagnetic topological insulator, which exhibits the quantum anomalous Hall effect, occurs in the strong spin-exchange regime.

Presenter: Nguyen Hong Son