Transport properties of high-performance all-Heusler Co 2CrSi/ Cu 2CrAl/Co 2CrSi giant magnetoresistance device

Abstract

Transport properties of giant magnetoresistance (MR) junction consisting of trilayer Co 2CrSi/Cu 2CrAl/Co 2CrSi Heusler alloys (L2 1) are studied using first-principles approach based on density functional theory and the non-equilibrium Green's function method. Highly conductive channels are found in almost the entire k-plane when the magnetizations of the electrodes are parallel, while they are completely blocked in the antiparallel configuration, which leads to a high magnetoresistance ratio (the pessimistic MR ratio is nearly 100%). Furthermore, the calculated I-V curve shows that the device behaves as a good spin valve with a considerable disparity in currents under the parallel and antiparallel magnetic configurations of the electrodes. The Co 2CrSi/Cu 2CrAl/ Co 2CrSi junction could be useful for high-performance all-metallic current-perpendicular-to-plane giant magnetoresistance reading head for the next generation high density magnetic storage. © 2012 American Institute of Physics.