Giant doping response of magnetic anisotropy in MnTe
Duncan H. Moseley, Keith M. Taddei, Jiaqiang Yan, Michael A. McGuire, Stuart Calder, Md Mobarak Hossain Polash, Daryoosh Vashaee, Xiaofan Zhang, Huaizhou Zhao, David Parker, R. S. Fishman, Raphaël P. Hermann
Abstract
The authors show that minuscule amounts of Li suffice to tune antiferromagnetic MnTe from an easy-plane to easy-axis material. Upon heating towards the N\'eel temperature of 307 K, the spins do not gradually rotate back to a planar orientation, and instead maintain their axial orientation up to a relatively high temperature of 260 K, before quickly switching back to a planar orientation and crossing into the paramagnetic phase. Calculations indicate MnTe bears two competing magnetic ground states which can be manipulated by slightly shifting the Fermi level via Li-doping. Easy manipulation of the spins in MnTe could have significant implications for future spintronic devices and materials.