Spin Hall magnetoresistance in an ultrathin Co2FeAl system

• Spin Hall magnetoresistance (SMR) is observed in an ultrathin Co2FeAl layer covered by a thin Pt film.
• Using a phenomenological model, angle dependences of SMR are derived which are coincident with both reported and our results very well.
• Magnetic insulator layer is not a requisite for the observation of SMR.

Spin Hall magnetoresistance (SMR) is observed in an ultrathin Co2FeAl layer covered by a thin Pt film. The Co2FeAl 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.