Temperature- and Bias-dependence of magnetoresistance in doped manganite thin film trilayer junctions

摘要

Thin film trilayer junction of La$%_{0.67}$Sr$_{0.33}$MnO$_3$ - SrTiO$_3$ -La$_{0.67}$Sr$_{0.33}$MnO$_3$ shows a factor of 9.7 change in resistance, in amagnetic field around 100 Oe at 14K. The junction magnetoresistance is bias andtemperature dependent. The energy scales associated with bias and temperaturedependence are an order of magnitude apart. The same set of energies alsodetermine the bias and temperature dependence of the differential conductanceof the junction. We discuss these results in terms of metallic clusterinclusions at the junction-barrier interface.