Room Temperature Skyrmions in Strain-Engineered FeGe thin films.

Autor: Budhathoki S; Department of Physics and Astronomy, University of Alabama, Tuscaloosa AL 35487, U.S.A., Sapkota A; Department of Physics and Astronomy, University of Alabama, Tuscaloosa AL 35487, U.S.A., Law KM; Department of Physics and Astronomy, University of Alabama, Tuscaloosa AL 35487, U.S.A., Ranjit S; Department of Physics and Astronomy, University of Alabama, Tuscaloosa AL 35487, U.S.A., Nepal B; Department of Physics and Astronomy, University of Alabama, Tuscaloosa AL 35487, U.S.A., Hoskins BD; Physical Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, MD 20899, U.S.A., Thind AS; Institute of Materials Science Engineering, Washington University in St. Louis, One Brookings Drive, St. Louis, MO 63130, U.S.A., Borisevich AY; Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN 37831, U.S.A., Jamer ME; Physics Department, United States Naval Academy, Annapolis, MD 21402, U.S.A., Anderson TJ; Naval Research Laboratory, Washington, DC 20375, U.S.A., Koehler AD; Naval Research Laboratory, Washington, DC 20375, U.S.A., Hobart KD; Naval Research Laboratory, Washington, DC 20375, U.S.A., Stephen GM; Physics Department, Northeastern University, Boston, MA 02115, U.S.A., Heiman D; Physics Department, Northeastern University, Boston, MA 02115, U.S.A., Mewes T; Department of Physics and Astronomy, University of Alabama, Tuscaloosa AL 35487, U.S.A., Mishra R; Institute of Materials Science Engineering, Washington University in St. Louis, One Brookings Drive, St. Louis, MO 63130, U.S.A.; Department of Mechanical Engineering Materials Science, Washington University in St. Louis, One Brookings Drive, St. Louis, MO 63130, U.S.A., Gallagher JC; U.S. Naval Research Laboratory, Washington, DC 20375, U.S.A., Hauser AJ; Department of Physics and Astronomy, University of Alabama, Tuscaloosa AL 35487, U.S.A.
Jazyk: angličtina
Zdroj: Physical review. B [Phys Rev B] 2020 Jun; Vol. 101 (22).
DOI: 10.1103/physrevb.101.220405
Abstrakt: Skyrmions hold great promise for low-energy consumption and stable high density information storage, and stabilization of the skyrmion lattice (SkX) phase at or above room temperature is greatly desired for practical use. The topological Hall effect can be used to identify candidate systems above room temperature, a challenging regime for direct observation by Lorentz electron microscopy. Atomically ordered FeGe thin films are grown epitaxially on Ge(111) substrates with ~ 4 % tensile strain. Magnetic characterization reveals enhancement of Curie temperature to 350 K due to strain, well above the bulk value of 278 K. Strong topological Hall effect was observed between 10 K and 330 K, with a significant increase in magnitude observed at 330 K. The increase in magnitude occurs just below the Curie temperature, a similar relative temperature position as the onset of Skx phase in bulk FeGe. The results suggest that strained FeGe films may host a SkX phase above room temperature when significant tensile strain is applied.
Databáze: MEDLINE