Exchange bias effect modulated anisotropic magnetoresistance in Fe/YMnO3 multiferroic bilayers

• Multiferroic bilayers of Fe/YMnO3 were prepared by magnetron sputtering.
• An exchange bias effect was discovered in these multiferroic bilayers.
• The exchange bias effect lead to phase shift and asymmetry of AMR curves.
• We report an exchange bias effect mediated AMR properties.

The effects of the interfacial coupling on the magnetic and magnetotransport properties of Fe/YMnO3 multiferroic bilayers were investigated through the dependence of exchange bias effect on the ferromagnetic layer thickness and temperature. A transition of anisotropic magnetoresistance (AMR) behaviors from a heart-shape-like to a sin2(φa)sin2(φa) dependence was acquired by mediating the competition between external magnetic field and exchange bias field. Furthermore, the exchange bias field produces a torque with opposite effect during the clockwise and anticlockwise rotation process of the external magnetic field, which leads to a phase shift and asymmetry of AMR curves. Our work shows an effective way of controlling the magnetotransport properties by interfacial coupling effect in ferromagnet/multiferroic systems.