"Spin-dependent transport across Co/LaAlO3/SrTiO3 heterojunctions "

Adrian G. Swartz: Satoshi Harashima, Yanwu Xie, Di Lu, Bongju Kim, Christopher Bell, Yasuyuki Hikita and Harold Y. Hwang; Applied Physics Letters, 07/23/2014.

Additional Authors: Satoshi Harashima, Yanwu Xie, Di Lu, Bongju Kim, Christopher Bell, Yasuyuki Hikita and Harold Y. Hwang

Abstract:

The conducting interface formed between LaAlO3 and SrTiO3 exhibits high electron mobility, tunable carrier densities, and is theoretically predicted to have long spin lifetimes. Thus, the LaAlO3/SrTiO3 heterostructure is a promising system for the transportation of spin information. We have investigated spin-dependent transport across Co/LaAlO3/SrTiO3 heterostructures using an all electrical three terminal geometry and observed Lorentzian magnetoresistance typically associated with Hanle spin dephasing. However, such a picture fails to explain all the experimentally observed behavior. Further, experiments with spin-unpolarized Au/LaAlO3/SrTiO3 heterojunctions support an alternative scenario involving current modulation by spin-dependent transport through defect states in the LaAlO3 barrier.