| AVS 66th International Symposium & Exhibition | |
| Thin Films Division | Friday Sessions |
| Session TF-FrM |
| Session: | Theory and Characterization of Thin Film Properties |
| Presenter: | Adam Hauser, The University of Alabama |
| Authors: | A.J. Hauser, The University of Alabama S. Budhathoki, The University of Alabama K. Law, The University of Alabama S. Ranjit, The University of Alabama A. Sapkota, The University of Alabama A. Thind, Washington University in St. Louis R. Mishra, Washington University in St. Louis D. Heiman, Northeastern University M.E. Jamer, United States Naval Acadamy A. Borisevich, Oak Ridge National Laboratory T. Mewes, The University of Alabama J. Gallagher, U.S. Naval Research Laboratory |
| Correspondent: | Click to Email |
The need to control and manipulate magnetic spin in nonvolatile memory applications drives exploration of new magnetic materials with non-uniformly ordered magnetic phases. Of particular interest are materials with inversion asymmetry, most commonly found in non-centrosymmetric space groups. Our group has successfully grown epitaxial B20 FeGe films with 4% tensile strain on a Ge(111) substrate by Sputter Beam Epitaxy, an off-axis magnetron sputtering technique in which beam-shaping, shutter control, and QCM-guided flux control of off-axis, direct-current (DC) magnetron sputter sources are employed upon high-purity elemental Fe and Ge targets in ultra-high vacuum. QCM control is modified to relative atomic ratios, and film compositions are confirmed by energy dispersive x-ray spectroscopy (EDS) and Rutherford Backscattering (RBS). X-ray diffractometry has confirmed that the films are single-crystal and phase pure, with near-substrate-limited rocking curve (FWHM 0.07º) and strong Keissig fringes in x-ray reflectometry. We find no evidence of strain relaxation up to 110nm, and off-axis XRD and HAADF STEM confirm the B20 phase necessary for the Skyrmionic phase. A strain-enhanced TC = 350K by SQUID magnetometry and a clear Topological Hall effect (THE) signature observed at 330K suggest potential for Skyrmionic behavior at or above room temperature in a single layer thin film. Direct observation is required for confirmation of a Skyrmion lattice phase.