  Ferroelectric and photovoltaic properties of BiFeO3/LaFeO3 superlattices
grown by pulsed laser deposition have been investigated being the bilayer
thickness). For a high concentration of BiFeO3 a ferroelectric state is
observed simultaneously with a switchable photovoltaic response. In contrast
for certain concentration of LaFeO3 a non-switchable photovoltaic effect is
evidenced. Such modulation of the PV response in the superlattices is
attributed to the ferroelectric to paraelectric phase transition which is
controlled with the increase of x. Remarkably, concomitant to this change of PV
mechanism, a change of the conduction mechanism also seems to take place from a
bulk-limited to an interface-limited transport as x increases.
