Quantum anomalous Hall effect in doped ternary chalcogenide topological insulators TlBiTe2 and TlBiSe2

Ternary Chalcogenide TlBiTe2 and TlBiSe2 have been proved to be promising topological insulators. In the present work, the occurrence of quantum anomalous Hall effect for a model Hamiltonian with ferromagnetic order is predicted. The first-principle calculations reveal that Cr is the best candidate to induce the ferromagnetic order in the insulating phase among X (X = Ti, Cr, Fe, and Au). The magnetic order in insulating phase arises from the spin polarization of substitutional Cr atoms and the free carriers are not needed for the formation of the substantial ferromagnetic coupling. These are very significant for the dissipationless devices in spintronics. (C) 2011 American Institute of Physics. [doi:10.1063/1.3645624]