Switchable photovoltaic and polarization modulated rectification in Si-integrated Pt-(Bi0.9Sm0.1)(Fe0.97Hf0.03)O3-LaNiO3 heterostructures

Abstract

We studied switchable photovoltaic and photo-diode characteristics of Pt (Bi0.9Sm0.1)(Fe0.97Hf0.03)O3 LaNiO3 (Pt BSFHO LNO) heterostructures integrated on Si (100). The directions of photocurrent (JSC) and rectification are found to be reversibly switchable after applying external poling voltages. In pristine state, metal-ferroelectric-metal capacitor Pt BSFHO LNO shows JSC 32 microAmp cm2 and VOC 0.04 V, which increase to maximum value of JSC 303 ( 206) microAmp cm2 and VOC 0.32 (0.26) V after upward (downward) poling at 8 V. We believe that Schottky barrier modulation by polarization flipping at Pt BSFHO interface could be a main driving force behind switchable photovoltaic and rectifying diode characteristics of Pt BSFHO LNO heterostructures.