The magnetic structure and phase diagram of the layered ferromagnetic compound Fe3GeTe2 has been investigated by a combination of synthesis, x-ray and neutron diffraction, high resolution microscopy, and magnetization measurements. Single crystals were synthesized by self-flux reactions, and single crystal neutron diffraction finds ferromagnetic order with moments of 1.11(5)μB/Fe aligned along the c-axis at 4K. These flux-grown crystals have a lower Curie temperature Tc≈150K compared to crystals previously grown by vapor transport (Tc=220K). The difference is a reduced Fe content in the flux grown crystals, as illustrated by the behavior observed in a series of polycrystalline samples. As Fe-content decreases, so does the Curie temperature, magnetic anisotropy, and net magnetization. In addition, Hall effect and thermoelectric measurements on flux-grown crystals suggest multiple carrier types contribute to electrical transport in Fe3−xGeTe2 and structurally-similar Ni3−xGeTe2.
@article{arxiv.1508.06959,
title = {Magnetic structure and phase stability of the van der Waals bonded ferromagnet Fe3-xGeTe2},
author = {Andrew F. May and Stuart Calder and Claudia Cantoni and Huibo Cao and Michael A. McGuire},
journal= {arXiv preprint arXiv:1508.06959},
year = {2016}
}
Comments
accepted version to be published in PRB; corrections made, includes Supplemental information