Spin Hall magnetoresistance in an ultrathin Co2FeAl system

Abstract

a b s t r a c tSpin Hall magnetoresistance (SMR) is observed in an ultrathin Co 2 FeAl layer covered by a thin Pt film. The Co 2 FeAl layer grown on a MgO substrate should be too thin to be continuous. The result reveals that the magnetic insulator layer, such as yttrium iron garnet (YIG) substrate which is frequently used so far, is actually not a requisite for the observation of SMR. This work may greatly help to understand the true nature of SMR effect.

Interface-induced spin Hall magnetoresistance enhancement in Pt-based tri-layer structure

“… 31 used ferromagnetic metal CoFeB to replace the FMI in the bilayer structure. Their results show that the SMR ratio of HM/FM bilayer structure is one order of magnitude higher than the HM/FMI bilayer 32 – 34 . These results have highly increased the application possibility of the SMR-related effect in spintronics.…”

Impact of Symmetry on Anisotropic Magnetoresistance in Textured Ferromagnetic Thin Films

“…As also pointed out by Zou et al [45] the structural properties, particularly the crystallinity of the films, are mandatory for a profound interpretation of MR data; however, they are often disregarded or not considered [34,[40][41][42][55][56][57][58][59] even in carefully performed studies [60,61]. Frequently, Δρ op signatures are ad hoc interpreted to be a fingerprint of the SMR while not thoroughly proven whether crystalline or interfacial AMR effects exist [34,[39][40][41][42][55][56][57][58][59]62]. The studies particularly lack an appropriate modeling of the electronic transport in all-metallic layered structures including the consideration of interface-scattering processes [39][40][41][42][55][56][57][58][59][60][61]63].…”

“…Signatures of Δρ ip;interface and Δρ op;interface were recently observed in various metallic layered structures [32][33][34][35][36][37][38][39][40][41][42][43][44].…”

“…Since the first pioneering experiment one branch of research deals with investigating the SMR in all-metallic multilayers; however, the outcome is not conclusive. As also pointed out by Zou et al [45] the structural properties, particularly the crystallinity of the films, are mandatory for a profound interpretation of MR data; however, they are often disregarded or not considered [34,[40][41][42][55][56][57][58][59] even in carefully performed studies [60,61]. Frequently, Δρ op signatures are ad hoc interpreted to be a fingerprint of the SMR while not thoroughly proven whether crystalline or interfacial AMR effects exist [34,[39][40][41][42][55][56][57][58][59]62].…”

“…Frequently, Δρ op signatures are ad hoc interpreted to be a fingerprint of the SMR while not thoroughly proven whether crystalline or interfacial AMR effects exist [34,[39][40][41][42][55][56][57][58][59]62]. The studies particularly lack an appropriate modeling of the electronic transport in all-metallic layered structures including the consideration of interface-scattering processes [39][40][41][42][55][56][57][58][59][60][61]63]. Properly correcting for the current shunt through paramagnetic layers provides the feasibility for the separation of interface and bulklike MR contributions [30], which is a necessary prerequisite to check for the validity of Eq.…”