Magnetocapacitance at the Ni/BiInO₃ Schottky Interface

We report the observation of a magnetocapacitance effect at the interface between Ni and epitaxial nonpolar BiInO 3 thin films at room temperature. A detailed surface study using X-ray photoelectron spectroscopy (XPS) reveals the formation of an intermetallic Ni–Bi alloy at the Ni/BiInO 3 interface and a shift in the Bi 4f and In 3d core levels to higher binding energies with increasing Ni thickness. The latter infers band bending in BiInO 3, corresponding to the formation of a p-type Schottky barrier. The current–voltage characteristics of the Ni/BiInO 3 /(Ba,Sr)RuO 3 /NdScO 3 (110) heterostructure show a significant dependence on the applied magnetic field and voltage cycling, which can be attributed to voltage-controlled band bending and spin-polarized charge accumulation in the vicinity of the Ni/BiInO 3 interface. The magnetocapacitance effect can be realized at room temperature without involving multiferroic materials.