Photovoltaic effect and enhanced magnetization in 0.9(BiFeO₃)–0.1(YCrO₃) composite thin film fabricated using sequential pulsed laser deposition

We report on the photovoltaic effect and multiferroic properties of a 0.9(BiFeO₃)–0.1(YCrO₃) composite thin film deposited on a Pt/TiO₂/SiO₂/Si substrate by sequential ablation of BiFeO₃ and YCrO₃ ceramic targets using pulsed laser deposition. The desired composition of the composite was achieved by controlling the ablation time of respective targets. As confirmed by the x-ray diffraction pattern the resultant film was found to be polycrystalline in nature and composed of a mixture of both rhombohedral BiFeO₃ and orthorhombic YCrO₃ phases. Interesting multiferroic properties in terms of an enhanced saturation magnetization of ∼14 emu cm⁻³ and the remnant polarization of ∼4.5 µC cm⁻² were observed where the enhancement in magnetization as compared to pristine BiFeO₃ could be attributed to the super-exchange interaction between Fe and Cr-ions. The photovoltaic properties of the composite thin film were studied under white light illumination in both top–bottom and lateral electrode configurations. Short circuit current densities (J_SC) = 1.48 µA cm⁻² and 0.44 µA cm⁻², and open circuit voltages (V_OC) = 0.51 V and 0.32 V were observed in top–bottom and lateral electrode configurations, respectively. (paper)