| 21. |
- Magnus, Fridrik, et al.
(författare)
-
Tuneable exchange-spring stiffness in amorphous magnetic trilayer structures
- 2021
-
Ingår i: Journal of Physics. - : Institute of Physics Publishing (IOPP). - 0953-8984 .- 1361-648X. ; 33:44
-
Tidskriftsartikel (refereegranskat)abstract
- We investigate the magnetic properties of amorphous Sm10Co90/Co-60(Al70Zr30)(40)/Co-85(Al70Zr30)(15) exchange-spring magnet trilayers. The magnetically soft Co-85(Al70Zr30)(15) layer is coupled to the magnetically hard Sm10Co90 layer through the weakly magnetic low-T (c) Co-60(Al70Zr30)(40) spacer layer. The strength of the coupling can be controlled with temperature and the coupling persists above the intrinsic T (c) of the spacer layer due to a long-range magnetic proximity effect. Polarized neutron reflectivity is used to examine the magnetic profile of the trilayers during magnetization reversal. A two-step switching occurs, with the switching angle of the soft layer strongly dependent on the strength of the coupling. In the strong coupling regime a magnetic state can be achieved where the soft layer magnetization is perpendicular to the hard layer whereas in the weak coupling regime the soft layer reverses fully.
|
|
| 22. |
- Meshkian, Rahele, et al.
(författare)
-
A magnetic atomic laminate from thin film synthesis: (Mo0.5Mn0.5)2GaC
- 2015
-
Ingår i: APL Materials. - : American Institute of Physics (AIP): Open Access Journals / AIP Publishing LLC. - 2166-532X. ; 3:7
-
Tidskriftsartikel (refereegranskat)abstract
- We present synthesis and characterization of a new magnetic atomic laminate: (Mo0.5Mn0.5)(2)GaC. High quality crystalline films were synthesized on MgO(111) substrates at a temperature of similar to 530 degrees C. The films display a magnetic response, evaluated by vibrating sample magnetometry, in a temperature range 3-300 K and in a field up to 5 T. The response ranges from ferromagnetic to paramagnetic with change in temperature, with an acquired 5T-moment and remanent moment at 3 K of 0.66 and 0.35 mu(B) per metal atom (Mo and Mn), respectively. The remanent moment and the coercive field (0.06 T) exceed all values reported to date for the family of magnetic laminates based on so called MAX phases.
|
|
| 23. |
- Meshkian, Rahele, et al.
(författare)
-
Theoretical stability, thin film synthesis and transport properties of the Mon+1GaCn MAX phase
- 2015
-
Ingår i: Physica Status Solidi. Rapid Research Letters. - : Wiley. - 1862-6254 .- 1862-6270. ; 9:3, s. 197-201
-
Tidskriftsartikel (refereegranskat)abstract
- The phase stability of Mon +1GaCn has been investigated using ab-initio calculations. The results indicate stability for the Mo2GaC phase only, with a formation enthalpy of 0.4 meV per atom. Subsequent thin film synthesis of Mo2GaC was performed through magnetron sputtering from elemental targets onto Al2O3 [0001], 6H-SiC [0001] and MgO [111] substrates within the temperature range of 500 degrees C and 750 degrees C. High structural quality films were obtained for synthesis on MgO [111] substrates at 590 degrees C. Evaluation of transport properties showed a superconducting behavior with a critical temperature of approximately 7 K, reducing upon the application of an external magnetic field. The results point towards the first superconducting MAX phase in thin film form.
|
|
| 24. |
- Mockuté, Aurelija, et al.
(författare)
-
Structural and magnetic properties of (Cr1-xMnx)(5)Al-8 solid solution and structural relation to hexagonal nanolaminates
- 2014
-
Ingår i: Journal of Materials Science. - : Springer Verlag (Germany). - 0022-2461 .- 1573-4803. ; 49:20, s. 7099-7104
-
Tidskriftsartikel (refereegranskat)abstract
- Electron microscopy is used to reveal the competitive epitaxial growth of bcc structure (Cr1-x Mn (x) )(5)Al-8 and (Cr1-y Mn (y) )(2)AlC [M (n+1)AX (n) (MAX)] phase during both magnetron sputtering and arc deposition. X-ray diffraction theta-2 theta measurements display identical peak positions of (000n)-oriented MAX phase and (Cr1-x Mn (x) )(5)Al-8, due to the interplanar spacing of (Cr1-x Mn (x) )(5)Al-8 that matches exactly half a unit cell of (Cr1-y Mn (y) )(2)AlC. Vibrating sample magnetometry shows that a thin film exclusively consisting of (Cr1-x Mn (x) )(5)Al-8 exhibits a magnetic response, implying that the potential presence of this phase needs to be taken into consideration when evaluating the magnetic properties of (Cr, Mn)(2)AlC.
|
|
| 25. |
- Mockuté, Aurelija, et al.
(författare)
-
Synthesis and characterization of arc deposited magnetic (Cr,Mn)(2)AlC MAX phase films
- 2014
-
Ingår i: Physica Status Solidi. Rapid Research Letters. - : Wiley. - 1862-6254 .- 1862-6270. ; 8:5, s. 420-423
-
Tidskriftsartikel (refereegranskat)abstract
- (Cr1-xMnx)(2)AlC MAX phase thin films were synthesized by cathodic arc deposition. Scanning transmission electron microscopy including local energy dispersive X-ray spectroscopy analysis of the as-deposited films reveals a Mn incorporation of as much as 10 at% in the structure, corresponding to x = 0.2. Magnetic properties were characterized with vibrating sample magnetometry, revealing a magnetic response up to at least room temperature. We thus verify previous theoretical predictions of an antiferromagnetic or ferromagnetic ground state for Cr2AlC upon alloying with Mn. ((c) 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
|
|
| 26. |
- Moubah, Reda, et al.
(författare)
-
Anisotropic Magnetostriction and Domain Wall Motion in Sm10Co90 Amorphous Films
- 2013
-
Ingår i: APPL PHYS EXPRESS. - 1882-0778. ; 6:5, s. 053004-
-
Tidskriftsartikel (refereegranskat)abstract
- We show that Sm10Co90 amorphous films exhibit anisotropic magnetostriction effects when a magnetic field is applied perpendicular to the imprinted easy axis of magnetization. At low applied fields (0-100 mT), we observe strong anisotropy in the field response. Parallel to the applied field, the strain scales linearly with the applied field while the strain perpendicular to the field direction ( easy axis) is close to the detection limit. This behavior is accompanied by zigzag domain wall motion with the corners pointing along the easy axis. The origin of the anisotropic magnetostriction is discussed.
|
|
| 27. |
- Moubah, Reda, et al.
(författare)
-
Antisymmetric magnetoresistance in SmCo5 amorphous films with imprinted in-plane magnetic anisotropy
- 2014
-
Ingår i: Journal of Applied Physics. - : AIP Publishing. - 0021-8979 .- 1089-7550. ; 115:5, s. 053911-
-
Tidskriftsartikel (refereegranskat)abstract
- We report on magnetoresistance measurements in SmCo5 amorphous films with a giant imprinted magnetic anisotropy. At low applied field parallel to the easy axis, the magnetoresistance exhibits a hysteretic, square, and antisymmetric shape. The antisymmetry in the magnetoresistance is a result of the non-uniform distribution of the magnetization direction over the sample in conjunction with the extraordinary Hall effect. Moreover, the combination of anisotropic magnetoresistance measurements and magnetic domain imaging demonstrates that the symmetry depends on the magnetization orientation with respect to the applied field.
|
|
| 28. |
- Moubah, Reda, et al.
(författare)
-
Discrete Layer-by-Layer Magnetic Switching in Fe/MgO(001) Superlattices
- 2016
-
Ingår i: Physical Review Applied. - : American physical society. - 2331-7019. ; 5:4
-
Tidskriftsartikel (refereegranskat)abstract
- We report on a discrete layer-by-layer magnetic switching in Fe/MgO superlattices driven by an antiferromagnetic interlayer exchange coupling. The strong interlayer coupling is mediated by tunneling through MgO layers with thicknesses up to at least 1.8 nm, and the coupling strength varies with MgO thickness. Furthermore, the competition between the interlayer coupling and magnetocrystalline anisotropy stabilizes both 90 degrees and 180 degrees periodic alignment of adjacent layers throughout the entire superlattice. The tunable layer-by-layer switching, coupled with the giant tunneling magnetoresistance of Fe/MgO/Fe junctions, is an appealing combination for three-dimensional spintronic memories and logic devices.
|
|
| 29. |
- Moubah, Reda, et al.
(författare)
-
Strain enhanced magnetic anisotropy in SmCo/BaTiO3 multiferroic heterostructures
- 2014
-
Ingår i: Journal of Applied Physics. - : AIP Publishing. - 0021-8979 .- 1089-7550. ; 115:5, s. 053905-
-
Tidskriftsartikel (refereegranskat)abstract
- We report on the changes in magnetic properties of SmCo/BaTiO3 multiferroic heterostructures as the BaTiO3 substrate undergoes its structural phase transitions. The observations show that the macroscopic magnetization of the SmCo film is affected by the structural phase transitions of the BaTiO3 substrate. Kerr microscopy images show that the magnetic domains of SmCo films have a zigzag shape but their shape is not influenced by the strain transferred from the substrate during the structural phase transitions. Analysis of the magnetoelastic energy shows that the macroscopic change of the magnetization is accompanied by an enhancement of the magnetic anisotropy for the orthorhombic phase of the BaTiO3 substrate and not a change in symmetry of the anisotropy.
|
|
| 30. |
- Moubah, Reda, et al.
(författare)
-
Strain induced changes in magnetization of amorphous Co95Zr5 based multiferroic heterostructures
- 2013
-
Ingår i: AIP Advances. - : AIP Publishing. - 2158-3226. ; 3:2, s. 022113-
-
Tidskriftsartikel (refereegranskat)abstract
- A clear change in the magnetic anisotropy in a layer of amorphous Co95Zr5 is obtained at the orthorhombic phase transition of the BaTiO3 substrate. The use of an amorphous buffer layer between the ferroelectric substrate and amorphous magnetic film shows that bulk strain governs the change in themagnetic anisotropy of our ferromagnetic-ferroelectric heterostructure. Moreover, we show that the thermal magnetization curves exhibit anisotropic behavior.
|
|
