Year: 2023
Type: article
Abstract: We reveal in this study the fundamental low-energy landscape in the ferrimagnetic ${\mathrm{Sr}}_{2}\mathrm{CrRe}{\mathrm{O}}_{6}$ double perovskite and describe the underlying mechanisms responsible for the three low-energy excitations below 1.4 eV. Based on resonant inelastic x-ray scattering and magnetic dynamics calculations, and experiments collected from both ${\mathrm{Sr}}_{2}\mathrm{CrRe}{\mathrm{O}}_{6}$ powders and epitaxially strained thin films, we reveal a strong competition between spin-orbit coupling, Hund's coupling, and the strain-induced tetragonal crystal field. We also demonstrate that a spin-flip process is at the origin of the lowest excitation at 200 meV, and we bring insights into the predicted presence of orbital ordering in this material. We study the nature of the magnons through a combination of ab initio and spin-wave theory calculations, and show that two nondegenerate magnon bands exist and are dominated either by rhenium or chromium spins. The rhenium band is found to be flat at about 200 meV (\ifmmode\pm\else\textpm\fi{}25 meV) through X-L-W-U high-symmetry points and is dispersive toward \ensuremath{\Gamma}.
Language: Latvian
Field: Materials Science
Domain: Physical Sciences
Open Access status: green
Funders: National Science Foundation, U.S. Department of Energy, Yale University, Office of Science, Materials Research Science and Engineering Center, Harvard University, Division of Materials Research, Basic Energy Sciences, Air Force Office of Scientific Research, Argonne National Laboratory, Brookhaven National Laboratory
Awards: G102163711, G107546177, G1210759672, G1285306620, G1286251239, G1313983767, G1523888516, G1664757510, G171842289, G1847291448, G1868695577, G2287611682, G241279073, G262962599, G266914229, G3062877667, G3075337988, G3249368838, G3262563802, G357145406, G3589692066, G3850097093, G426311843, G4516736450, G4662383146, G4972998915, G498139845, G513797252, G5387317844, G5417557083, G5535608740, G5633341255, G5765906131, G5956625161, G6733788163, G6848031779, G6918803902, G6965541988, G741291543, G7463374569, Center for Emergent Materials, an NSF MRSEC, G7583137537, G872144517, G969889393, G993149817
OpenAlex ID: W4385806147