Strain-modulated ferromagnetism and band gap of Mn doped Bi2Se3.

ABSTRACT: The quantized anomalous Hall effect (QAHE) have been theoretically predicted and experimentally confirmed in magnetic topological insulators (TI), but dissipative channels resulted by small-size band gap and weak ferromagnetism make QAHE be measured only at extremely low temperature (<0.1?K). Through density functional theory calculations, we systemically study of the magnetic properties and electronic structures of Mn doped Bi2Se3 with in-plane and out-of-plane strains. It is found that out-of-plane tensile strain not only improve ferromagnetism, but also enlarge Dirac-mass gap (up to 65.6?meV under 6% strain, which is higher than the thermal motion energy at room temperature ~26?meV) in the Mn doped Bi2Se3. Furthermore, the underlying mechanisms of these tunable properties are also discussed. This work provides a new route to realize high-temperature QAHE and paves the way towards novel quantum electronic device applications.

SUBMITTER: Qi S 

PROVIDER: S-EPMC4931584 | biostudies-literature | 2016 Jul

REPOSITORIES: biostudies-literature