Ferromagnetism and topological surface states of manganese doped Bi2Te3: insights from density-functional calculations.
Based on first-principles calculations, the electronic, magnetic, and topological characters of manganese (Mn) doped topological insulator Bi2Te3 were investigated. The Mn substitutionally doped Bi2Te3, where Mn atoms tend to be uniformly distributed, was shown to be p-type ferromagnetic, arising from hole-mediated Ruderman-Kittel-Kasuya-Yosida interaction. Mn doping leads to an intrinsic band splitting at Γ point, which is substantially different from that of nonmagnetic dopant. The topological surface state of Bi2Te3 is indeed gapped by Mn doping; however, the bulk conductance limits the appearance of an insulating state. Moreover, the n-type doping behavior of Bi2Te3 is derived from Mn entering into the van der Waals gap of Bi2Te3.
National Center for Nanoscience and Technology, Beijing 100190, People's Republic of China.
Yuanchang
Y
Li
Department of Materials Science and Nanoengineering, Rice University, Houston, Texas 77005, USA.
Xiaolong
X
Zou
Key Laboratory of Thermal Management Engineering and Materials, Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, People's Republic of China.
Jia
J
Li
Department of Physics, Tsinghua University, Beijing 100084, People's Republic of China.
Gang
G
Zhou