Magnetotransport in La0.7Sr0.3MnO3/CuCr2O4/Fe3O4 magnetic junctions

Abstract

We demonstrate distinct magnetic and resistive switching with junction magnetoresistance up to −6% in magnetic tunnel junctions with a CuCr2O4 barrier. Junction magnetoresistance is inversely related to barrier thickness and reveals a maximum at a finite applied bias that converges to zero bias at low temperatures for all barrier thicknesses. The non-monotonic bias dependence is attributed to a charge gap from the Fe3O4 electrode and possible spin filtering from the spin-split conduction band of the ferrimagnetic CuCr2O4 barrier.