Effect of film thickness on interfacial barrier of manganite-based heterojunctions

Interfacial barrier is a key factor that determines the performances of heterojunctions. In this work, we study the effect of manganite film thickness on the effective interfacial barrier for La0.67Sr0.33MnO3/Nb:SrTiO3 junctions. The barrier is extracted from the forward current-voltage characteristics. Our results demonstrate that the barrier decreases gradually from ∼0.85 eV to ∼0.60 eV when the film thickness decreases from 150 nm to 2 nm. The overall value of the barrier is only about 50% of the corresponding one determined from the photovoltaic effect. (rapid communication)