Anisotropic magnetoresistance and negative magnetoresistance for in-plane fields are compared for the LaAlO3/SrTiO3 interface and the symmetric Nb-doped SrTiO3 heterostructure. Both effects are exceptionally strong in LaAlO3/SrTiO3. We analyze their temperature, magnetic field, and gate voltage dependencies and find them to arise from a Rashba-type spin-orbit coupling with magnetic scatterers that have two contributions to their potential: spin exchange and Coulomb interaction. Atomic spin-orbit coupling is sufficient to explain the small effects observed in Nb-doped SrTiO3. These results clarify contradicting transport interpretations in SrTiO3 based heterostructures.
|Number of pages||5|
|Journal||Physical Review B: Condensed Matter and Materials Physics|
|Publication status||Published - 11 Sept 2012|
- LAALO3/SRTIO3 INTERFACE