Impact of the interface quality of Pt/YIG(111) hybrids on their spin Hall magnetoresistance
arXiv:1612.08150 · doi:10.1063/1.4973460
Abstract
We study the influence of the interface quality of Pt/YFeO(111) hybrids on their spin Hall magnetoresistance. This is achieved by exposing YFeO(111) single crystal substrates to different well-defined surface treatments prior to the Pt deposition. The quality of the YFeO(YIG) surface, the Pt/YIG interface and the Pt layer is monitored \textit{in-situ} by reflection high-energy electron diffraction and Auger electron spectroscopy as well as \textit{ex-situ} by atomic force microscopy and x-ray diffraction. To identify the impact of the different surface treatments on the spin Hall magnetoresistance, angle-dependent magnetoresistance measurements are carried out at room temperature. The largest spin Hall magnetoresistance is found in Pt/YIG fabricated by a two-step surface treatment consisting of a "piranha" etch process followed by an annealing step at C in pure oxygen atmosphere. Our data suggest that the small SMR in Pt/YIG without any surface treatments of the YIG substrate prior to Pt deposition is caused by a considerable carbon agglomeration at the YFeO surface.