Ferroelectric semiconducting oxides are promising platforms for energy-efficient devices based on polarization direction, such as ferroelectric random-access memories and field-effect transistors. Here, by exploiting a ferroelectric polarization-controlled $p\text{−}n$ junction established between a $p$-type ${\mathrm{Bi}}_2{\mathrm{FeCrO}}_6$ thin film and a Nb-doped ${\mathrm{SrTiO}}_3$ substrate, we demonstrate a nondestructive photovoltaic readout of the ferroelectric polarization direction. Using a conductive atomic force microscope coupled to a wavelength-tunable laser across the visible spectral range, it is shown that down-poled areas obtained by tip-induced domain writing generate a negligible short-circuit photocurrent, while up-poled areas produce large photocurrents with a clear dependence on illumination wavelength. An open-circuit voltage that increases logarithmically with laser power is also observed for the up-polarization state. These results establish a useful methodology for mapping ferroelectric photovoltaic effects and provide a promising perspective for future nonvolatile memory systems.

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• Optoelectronics
• Photoconductivity
• Photovoltaic absorbers
• Photovoltaic effect
• Surface & interfacial phenomena
• Thin-film photovoltaics
• Complex oxides
• Ferroelectrics
• Heterostructures
• Junctions
• Schottky barriers
• Solid-solid interfaces
• Atomic force microscopy
• Photoexcitation