Antiferromagnetic junctions: the model case of Cr wires

Antiferromagnetic systems have been intensively studied for technological purposes, as they can represent an alternative to conventional devices based on giant-magneto resistance (GMR) to Tunneling Magnetoresistance (TMR) effects. As a matter of fact, the absence of magnetic stray fields and the larger robustness can allow for the realization of a new-generation of magnetic memories with increased density and improved robustness and stability (MRAMS). In this picture, Cr is particularly appealing because it is the only elemental metal that is antiferromagnetic at room temperature. Unfortunately Cr has a small Spin-Orbit Coupling (SOC) and consequently a very small magnetic anisotropy. In this work we studied a series of model systems composed by chromium 1D wires. In order to further enhance the anisotropy, we interfaced Cr with atoms of heavier 5d metals, e.g. Au and Pt. On these systems we performed ab-initio calculations of electron transport using the Landauer-Buttiker approach and we studied the effect of different orientation of the local magnetization moments on the transmission function T(E). Our results show sizable effect on the ballistic current, that could render Cr suitable for antiferromagnetic-based memories and other spintronic devices.