Enhancement of Spin Polarization in a Transition Metal Oxide Ferromagnetic Nanodot Diode

Enhancement of spin polarization was observed in a transition metal oxide (Fe,Zn)(3)O-4/Nb-SrTiO3 ferromagnetic nanodot Schottky. The highly integrated oxide nanodot diodes were constructed using nanoimprint lithography based on a Mo lift-off method in combination with a pulsed laser deposition technique. The junction magnetoresistance of diodes increased as diode size increased. The spin polarization estimated from the thermionic emission model is enhanced from P = 0.74 in a conventional film to P = 0.89 in a nanodot diode whose size is 300 x 300 nm(2). The nanofabrication technique used here will enable us to construct superior transition metal oxide spintronic nanomaterial and nanodevices.