We electrically detect charge current induced spin polarization on the surface of a molecular beam epitaxy grown Bi2Te3 thin film in a two-terminal device with a ferromagnetic MgO/Fe contact and a nonmagnetic Ti/Au contact. The two-point resistance, measured in an applied magnetic field, shows a hysteresis tracking the magnetization of Fe. A theoretical estimate is obtained for the change in resistance on reversing the magnetization direction of Fe from coupled spin-charge transport equations based on the quantum kinetic theory. The order of magnitude and the sign of the hysteresis are consistent with the spin-polarized surface state of Bi2Te3.
Detection of current induced spin polarization in epitaxial Bi2Te3 thin film
Rik Dey, Anupam Roy, Tanmoy Pramanik, Amritesh Rai, Seung Heon Shin, Sarmita Majumder, Leonard F. Register, Sanjay K. Banerjee; Detection of current induced spin polarization in epitaxial Bi2Te3 thin film. Appl. Phys. Lett. 20 March 2017; 110 (12): 122403. https://doi.org/10.1063/1.4978691
Download citation file: