Tunnel barrier parameters and magnetoresistance in the parabolic band model - art. no. 144402

Tunnel magnetoresistance (MR) is studied in the framework of the parabolic band model. Coherent transport and electronic wave function interferences i n the barrier are shown to play an important role even for a single barrier . The influence of the barrier parameters on magnetoresistance and on its b ias dependence is compared with success to experiments. The shape of the ba rrier is then considered as it can account for asymmetries observed in MR(V ) curves. Finally, despite its simplicity, this model predicts qualitativel y the complex MR(V) observed in composite barriers.