Magnetocapacitance and exponential magnetoresistance in   manganite-titanate heterojunctions
  We present a rectifying manganite-titanate heterojunction exhibiting a magnetic field tunable depletion layer. This creates a large positive magnetocapacitance, a direct measure of the field-induced reduction of the effective depletion width across the junction. Furthermore, the reduction of the junction barrier shifts the forward bias characteristics, giving exponentially-enhanced differential magnetoresistance, occurring despite the absence of a spin filter. These results provide a unique probe of a Mott insulator/band insulator interface, and further suggest new electronic devices incorporating the magnetic field sensitivity of these strongly correlated electron materials. 
N. Nakagawa, M. Asai, Y. Mukunoki, T. Susaki, and H. Y. Hwang   (University of Tokyo)