Domain-wall photovoltaic effect in Fe-doped BaTiO3 single crystals

A single crystal of Fe (0.3%)-doped BaTiO3 was grown by a top-seeded solution growth method, and the photovoltaic (PV) properties (at 3.1eV) in a multi-domain state with a 90 degrees domain structure are investigated. We show that the overall behavior can be well understood by an analytical expression of the domain wall (DW)-PV effect superimposed on the bulk-PV effect. The fitting of photocurrents as a function of light polarization reveals that the offset component of the DW-PV effect is much larger than that of the bulk-PV effect, even though the volume fraction of the DW region is extremely small. A local electric field in the DW region is estimated to be several hundred kVcm(-1), which is three orders of magnitude higher than the effective field inside the domains.

Automated summary

Experimental study showed that Fe doping significantly affects the photovoltaic properties of BaTiO3 single crystal, with the DW-PV effect having a more significant impact on overall behavior than the bulk-PV effect, despite the small volume fraction of the DW region. The estimated local electric field in the DW region reaches several hundred kVcm(-1), three orders of magnitude higher than the effective field inside the domains.