Logarithmic singularities and quantum oscillations in magnetically doped topological insulators

Abstract

We report magnetotransport measurements on magnetically doped (Bi,Sb)2Te3 films grown by molecular beam epitaxy. In Hallbar devices, we observe logarithmic dependence of transport coefficients in temperature and bias voltage which can be understood to arise from electron -electron interaction corrections to the conductivity and self-heating. Submicron scale devices exhibit intriguing quantum oscillations at high magnetic fields with dependence on bias voltage. The observed quantum oscillations can be attributed to bulk and surface transport.

Quantum Oscillations in Ferromagnetic (Sb, V)2Te3 Topological Insulator Thin Films

“…So far, to our knowledge, there are only a few reports on the observation of quantum oscillations in magnetically doped TIs, such as V‐doped (Bi, Sb) 2 Te 3 , Sm‐doped Bi 2 Se 3 . [ 28,29 ] However, in all of those studies, the oscillations were only observed in longitudinal resistance. Furthermore, the systematical studies on the mechanism of the quantum oscillations in magnetically doped TIs is still lacking.…”

“…The results motivated the preparation of thin films of similar materials with the potential for FM order coexisting with high mobility topological surface states.So far, to our knowledge, there are only a few reports on the observation of quantum oscillations in magnetically doped TIs, such as V-doped (Bi, Sb) 2 Te 3 , Sm-doped Bi 2 Se 3 . [28,29] However,effective way of manipulating 2D surface states in magnetic topological insulators may open a new route for quantum technologies based on the quantum anomalous Hall effect. The doping-dependent evolution of the electronic band structure in the topological insulator Sb 2−x V x Te 3 (0 ≤ x ≤ 0.102) thin films is studied by means of electrical transport.…”

“…So far, to our knowledge, there are only a few reports on the observation of quantum oscillations in magnetically doped TIs, such as V-doped (Bi, Sb) 2 Te 3 , Sm-doped Bi 2 Se 3 . [28,29] However,…”