Gate-controlled spin injection at LaAlO3/SrTiO3 interfaces

Phys Rev Lett. 2012 May 4;108(18):186802. doi: 10.1103/PhysRevLett.108.186802. Epub 2012 Apr 30.


We report results of electrical spin injection at the high-mobility quasi-two-dimensional electron system (2-DES) that forms at the LaAlO3/SrTiO3 interface. In a nonlocal, three-terminal measurement geometry, we analyze the voltage variation associated with the precession of the injected spin accumulation driven by perpendicular or transverse magnetic fields (Hanle and inverted Hanle effect). The influence of bias and back-gate voltages reveals that the spin accumulation signal is amplified by resonant tunneling through localized states in the LaAlO3 strongly coupled to the 2-DES by tunneling transfer.