| 1. |
- Salikhov, R., et al.
(författare)
-
Enhanced spin-orbit coupling in tetragonally strained Fe-Co-B films
- 2017
-
Ingår i: Journal of Physics. - : Institute of Physics Publishing (IOPP). - 0953-8984 .- 1361-648X. ; 29:27
-
Tidskriftsartikel (refereegranskat)abstract
- Tetragonally strained interstitial Fe-Co-B alloys were synthesized as epitaxial films grown on a 20 nm thick Au0.55Cu0.45 buffer layer. Different ratios of the perpendicular to in-plane lattice constant c/a = 1.013, 1.034 and 1.02 were stabilized by adding interstitial boron with different concentrations 0, 4, and 10 at.%, respectively. Using ferromagnetic resonance (FMR) and x-ray magnetic circular dichroism (XMCD) we found that the total orbital magnetic moment significantly increases with increasing c/a ratio, indicating that reduced crystal symmetry and interstitial B leads to a noticeable enhancement of the effect of spin-orbit coupling (SOC) in the Fe-Co-B alloys. First-principles calculations reveal that the increase in orbital magnetic moment mainly originates from B impurities in octahedral position and the reduced symmetry around B atoms. These findings offer the possibility to enhance SOC phenomena - namely the magnetocrystalline anisotropy and the orbital moment - by stabilizing anisotropic strain by doping 4 at.% B. Results on the influence of B doping on the Fe-Co film microstructure, their coercive field and magnetic relaxation are also presented.
|
|
| 2. |
|
|
| 3. |
- Salikhov, R., et al.
(författare)
-
Magnetic properties of nanolaminated (Mo0.5Mn0.5)(2)GaC MAX phase
- 2017
-
Ingår i: Journal of Applied Physics. - : AMER INST PHYSICS. - 0021-8979 .- 1089-7550. ; 121:16
-
Tidskriftsartikel (refereegranskat)abstract
- The magnetic properties of hexagonal (Mo0.5Mn0.5)(2)GaC MAX phase synthesized as epitaxial films on MgO (111) substrates with the c-axis perpendicular to the film plane are presented. The analysis of temperature-dependent ferromagnetic resonance (FMR) and magnetometry data reveals a ferro-to paramagnetic phase transition at 220 K. The electrical transport measurements at 5K show a negative magnetoresistance of 6% in a magnetic field of 9 T. Further analysis confirms the spin-dependent scattering of charge carriers in this layered material. A small perpendicular (c-axis) magnetocrystalline anisotropy energy density (MAE) of 4.5 kJ/m(3) at 100K was found using FMR. Accordingly, (Mo0.5Mn0.5)(2)GaC behaves similar to the (Cr0.5Mn0.5)(2)GaC MAX phase as a soft magnetic material. The density functional theory calculations reveal that the sign and the amplitude of the MAE can be very sensitive to (Mo0.5Mn0.5)(2)GaC lattice parameters, which may explain the measured soft magnetic properties. Published by AIP Publishing.
|
|
| 4. |
- Tao, Quanzheng, et al.
(författare)
-
Atomically Layered and Ordered Rare-Earth i-MAX Phases : A New Class of Magnetic Quaternary Compounds
- 2019
-
Ingår i: Chemistry of Materials. - : American Chemical Society (ACS). - 0897-4756 .- 1520-5002. ; 31:7, s. 2476-2485
-
Tidskriftsartikel (refereegranskat)abstract
- In 2017, we discovered quaternary i-MAX phases atomically layered solids, where M is an early transition metal, A is an A group element, and X is C—with a (M12/3M21/3)2AC chemistry, where the M1 and M2 atoms are in-plane ordered. Herein, we report the discovery of a class of magnetic i-MAX phases in which bilayers of a quasi-2D magnetic frustrated triangular lattice overlay a Mo honeycomb arrangement and an Al Kagome lattice. The chemistry of this family is (Mo2/3RE1/3)2AlC, and the rare-earth, RE, elements are Ce, Pr, Nd, Sm, Gd, Tb, Dy, Ho, Er, Tm, and Lu. The magnetic properties were characterized and found to display a plethora of ground states, resulting from an interplay of competing magnetic interactions in the presence of magnetocrystalline anisotropy.
|
|
| 5. |
- Tao, Quanzheng, et al.
(författare)
-
Thin film synthesis and characterization of a chemically ordered magnetic nanolaminate (V,Mn)(3)GaC2
- 2016
-
Ingår i: APL Materials. - : AMER INST PHYSICS. - 2166-532X. ; 4:8
-
Tidskriftsartikel (refereegranskat)abstract
- We report on synthesis and characterization of a new magnetic nanolaminate (V,Mn)(3)GaC2, which is the first magnetic MAX phase of a 312 stoichiometry. Atomically resolved energy dispersive X-ray mapping of epitaxial thin films reveals a tendency of alternate chemical ordering between V and Mn, with atomic layers composed of primarily one element only. Magnetometry measurements reveal a ferromagnetic response between 50 K and 300 K, with indication of a magnetic ordering temperature well above room temperature. (C) 2016 Author(s).
|
|
