Abstract
Conventionally, the modulation of the intrinsic Weyl nodes in Weyl semimetals is challenging, due to topological protection. Here we report the structural dependence of the Weyl nodes in a Co2MnGa Heusler thin film via a temperature-dependent tetragonal distortion. The ability to manipulate these Weyl nodes allows for the control of the intrinsic electromagnetic properties. Temperature-dependent x-ray diffraction (XRD) measurements identify a compressive tetragonal distortion with decreasing temperature from 300 to 20 K. The calculated Weyl properties can be directly compared with experimental parameters through the temperature-dependent XRD measurements which show the intrinsic correlation between Weyl properties and important magnetic parameters. The microscopic momentum space properties of Weyl nodes such as the distance (dW), solid angle (ωW), tilt (φW), and nodal point energy (EW) directly affect the macroscopic observable properties such as exchange stiffness (A), magnetization (M), and effective anisotropy field (HKeff), as shown via structure-dependent density functional theory calculations. These predictions are experimentally observed as large variations in the bulk magnetization and effective anisotropy field as a function of temperature. These results highlight a unique degree of freedom in the control of macroscopic magnetic properties via the modulation of the intrinsic properties of Weyl nodes through structural distortions.
| Original language | English |
|---|---|
| Article number | 054419 |
| Journal | Physical Review B |
| Volume | 110 |
| Issue number | 5 |
| DOIs | |
| State | Published - Aug 1 2024 |
Funding
H.S. and M.H.P. acknowledge support from the U.S. Department of Energy, Office of Basic Energy Sciences, Division of Materials Science and Engineering under Award No. DE-FG02-07ER46438. N.S. would like to acknowledge the Department of Defense SMART program. The work of E.M.C. and M.M. was supported by the U.S. Department of Energy (DOE), Office of Science, Basic Energy Services (BES), Materials Sciences and Engineering Division. The work of J.G. and G.P. was supported by the Air Force Office of Scientific Research under Award No. FA9550-23-1-0132. J.G. and G.P. acknowledge support from the Max Planck Society through the Max Planck Partner Group Programme.