Site-specific order and magnetism in tetragonal Mn<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:msub><mml:mrow /><mml:mn>3</mml:mn></mml:msub></mml:math>Ga thin films

Rode, Karsten; Baâdji, N.; Betto, Davide; Lau, Yong‐Chang; Kurt, Hüseyin; Venkatesan, M.; Stamenov, Plamen; Sanvito, Stefano; Coey, J. M. D.; Fonda, Emiliano; Otero, Edwige; Choueikani, Fadi; Ohresser, P.; Porcher, Florence; André, G.

doi:10.1103/physrevb.87.184429

Cited by 88 publications

(103 citation statements)

References 39 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…3(a) various Fe concentrations. Previously, similar observations in tetragonal Mn 3−x Ga were attributed to the oscillatory exchange coupling between the first-and second-nearest Mn neighbors [29]. Our experimental observations suggest that similar situation is likely to happen in MFG, even in the presence of the additional magnetic Fe atoms.…”

Section: B Magnetic and Magnetotransport Propertiessupporting

confidence: 67%

“…Mn is present in both the 4d and 2b positions, and, for x > 1, the anisotropy constant changes sign, going from easy-axis to easy-plane. We have previously found [29] that for Mn 3 Ga the 4d site has perpendicular anisotropy, while the 2b site possesses in-plane anisotropy. Therefore, when the Mn 2b occupation is sufficiently high, the net magnetocrystalline anisotropy of Mn changes from easy-axis (due to 4d) to easyplane (due to 2b) in MFG.…”

Section: X-ray Absorption and Magnetic Circular Dichroismmentioning

confidence: 99%

“…Previously [29], we demonstrated that in manganesedeficient tetragonal Mn 3−x Ga films, the Ga vacancies are negligible and the Mn vacancies are distributed over the 2b and 4d sites, with a preference for the 2b positions. Here we use the film density, determined from the XRR, as the key parameter to examine whether this can be applied to MFG.…”

Section: A Structural Properties X-ray Diffraction and X-ray Reflecmentioning

confidence: 99%

See 2 more Smart Citations

Structure, site-specific magnetism, and magnetotransport properties of epitaxial D022 -structure Mn2FexGa thin

et al. 2017

Self Cite

View full text Add to dashboard Cite

Ferrimagnetic Mn 2 Fe x Ga (0.26 x 1.12) thin films have been characterized by x-ray diffraction, magnetometry, x-ray absorption spectroscopy, x-ray magnetic circular dichroism, and Mössbauer spectroscopy with the aim of determining the structure and site-specific magnetism of this tetragonal, D0 22 -structure Heusler compound. High-quality epitaxial films with low root-mean-square surface roughness (∼0.6 nm) are grown by magnetron cosputtering. The tetragonal distortion induces strong perpendicular magnetic anisotropy along the c axis with a typical coercive field μ 0 H ∼ 0.8 T and an anisotropy field ranging from 6 to 8 T. On increasing the Fe content x, substantial uniaxial anisotropy, K u 1.0 MJ m −3 , can be maintained over the full x range, while the magnetization of the compound is reduced from 400 to 280 kA m −1 . The total magnetization is almost entirelygiven by the sum of the spin moments originating from the ferrimagnetic Mn and Fe sublattices, with the latter being coupled ferromagnetically to one of the former. The orbital magnetic moments are practically quenched and have negligible contributions to the magnetization. The films with x = 0.73 exhibit an anomalous Hall angle of 2.5% and a Fermi-level spin polarization above 51%, as measured by point contact Andreev reflection. The Fe-substituted Mn 2 Ga films are tunable with a unique combination of high anisotropy, low magnetization, appreciable spin polarization, and low surface roughness, making them strong candidates for thermally stable spin-transfer-torque switching nanomagnets with lateral dimensions down to 10 nm.

show abstract

Section: B Magnetic and Magnetotransport Propertiessupporting

confidence: 67%

Section: X-ray Absorption and Magnetic Circular Dichroismmentioning

confidence: 99%

Section: A Structural Properties X-ray Diffraction and X-ray Reflecmentioning

confidence: 99%

See 1 more Smart Citation

Structure, site-specific magnetism, and magnetotransport properties of epitaxial D022 -structure Mn2FexGa thin

et al. 2017

Self Cite

View full text Add to dashboard Cite

show abstract

“…9 As the composition of the films is varied from x ¼ 0 to 1 (from Mn 3 Ga to Mn 2 Ga), Mn is primarily lost from the 2b position. Hence, the net magnetization increases with increasing x, and there is no compensation composition.…”

mentioning

confidence: 99%

“…These values and hence the resonance frequency can be controlled via the films' stoichiometry. Using previously obtained data from neutron scattering measurements on bulk Mn 3 Ga samples, 9 the frequency of the out-phasemode in Mn 3 Ga is predicted from Eq. (1), to lie in the region of 0.35 THz.…”

mentioning

confidence: 99%

Narrow-band tunable terahertz emission from ferrimagnetic Mn3-xGa thin films

Awari

Kovalev

Fowley

et al. 2016

Applied Physics Letters

Self Cite

View full text Add to dashboard Cite

Narrow-band terahertz emission from coherently excited spin precession in metallic ferrimagnetic Mn3-xGa Heusler alloy nanofilms has been observed. The efficiency of the emission, per nanometer film thickness, is comparable or higher than that of classical laser-driven terahertz sources based on optical rectification. The center frequency of the emission from the films can be tuned precisely via the film composition in the range of 0.20–0.35 THz, making this type of metallic film a candidate for efficient on-chip terahertz emitters. Terahertz emission spectroscopy is furthermore shown to be a sensitive probe of magnetic properties of ultra-thin films.

show abstract

Compensated Ferrimagnetic Tetragonal Heusler Thin Films for Antiferromagnetic Spintronics

et al. 2016

View full text Add to dashboard Cite

Spintronics is a large field of research that involves the generation, manipulation and detection of spin currents in magnetic heterostructures and the use of these currents to excite and to set the state of magnetic nano-elements. [1,2] The field of spintronics has focused on ferromagnetic thin film structures in which charge currents can be spin-polarized via interfacial and volume spin dependent scattering. However, ferromagnets produce magnetostatic dipole fields, which increase in size as devices are scaled to smaller dimensions. These must be minimized or eleminated to enable operation of spintronic field sensing and magnetic memories. [2] One way to do this is to take advantage of the phenomenon of long-range oscillatory interlayer coupling [3] to create synthetic antiferromagnetic heterostructures [1] or the use of ferrimagnetic materials such as rare-earthtransition metal alloys at their compensation point. [4] The latter ferrimagnetic materials are of special inerest because they can completely eliminate dipole fields volumetrically, even on the atomic scale. However, materials are needed that can operate over a wide temperature window and not solely at or in the vicinity of a compensation temperature. Here we show that Heusler compounds can be designed for this purpose.Heusler compounds, YZ X 2 (where X , Y are transition metals and Z is a main-group 2 element), are well known for their potential applications in spintronics, especially in spin-torque based devices. [5] These materials crystallize in both cubic and tetragonal crystal structures with multiple magnetic sub-lattices, and hence are good candidates for engineering a wide range of complex magnetic structures. In particular all the known tetragonal Heuslers are ferrimagnetic with at least two magnetic sub-lattices whose magnetizations are aligned anti-parallel to one another, or, as has been shown recently, can be non-collinear to one another. The Mn based tetragonal Heuslers are of particular interest because their magnetic ordering temperatures can be well above room temperature, but the magnetizations of their two sub-lattices are typically distinct, leading to a net uncompensated magnetization. One of the most interesting of these materials is Mn3Ga which has a Curie temperature of ~750 K. [6] By tuning the magnetization of the two sublattices in Mn3Ga by changes in composition, we propose that a fully compensated ferrimagnetic (CFI) Heusler is possible. To help identify the needed compositional variations we have carried out density functional calculations of the electronic structures of Mn3-xYxGa   1 0   x (at zero temperature) for the elements = Y Ni, Cu, Rh, Pd, Ag, Ir, Pt, Au, which are non-magnetic or nearly non-magnetic when substituted into Mn3Ga. We show that in all these cases it is theoretically possible to obtain a CFI , which we have experimentally validated for the case of Y=Pt.The present calculation is based on the experimental lattice parameters of the bulk Mn 3 Ga lattice. [6] We find that a compensated mag...

show abstract

Site-specific order and magnetism in tetragonal Mn3Ga thin films

Cited by 88 publications

References 39 publications

Structure, site-specific magnetism, and magnetotransport properties of epitaxial D022 -structure Mn2FexGa thin

Structure, site-specific magnetism, and magnetotransport properties of epitaxial D022 -structure Mn2FexGa thin

Narrow-band tunable terahertz emission from ferrimagnetic Mn3-xGa thin films

Compensated Ferrimagnetic Tetragonal Heusler Thin Films for Antiferromagnetic Spintronics

Contact Info

Product

Resources

About