Anomalous Nernst effect dependence on composition in Fe100-X Rh X alloys

Abstract We studied the anomalous Nernst effect in CsCl-type Fe100-X Rh X (X = 45, 48, 50, 52, 54, 60) with a thickness of 50 nm deposited on a thermally oxidized Si substrate. Samples with X < 48 certainly have a ferromagnetic phase, exhibiting the anomalous Nernst effect. The composition dependence of the anomalous Nernst coefficient S yx agreed with the transverse thermoelectric conductivity α yx. |S yx | and |α yx | were maximized at X = 48, which has a ferromagnetic state close to the phase transition state. The maximization of |α yx | at X = 48 can be explained using band structure-based calculations , where |α yx | rapidly increases near the phase transition.

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Electronic Properties and Magnetic Phase Transition in Half-Heusler Compound Fe1-XCuxMnSb

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.479-481.403 ◽

2012 ◽

Vol 479-481 ◽

pp. 403-406

Author(s):

Bo Wu ◽

Xiu De Yang ◽

Song Zhang

Keyword(s):

Phase Transition ◽

Magnetic Phase Transition ◽

Density Functional ◽

Large Deviation ◽

Magnetic Phase ◽

Magnetic Coupling ◽

Ferromagnetic State ◽

Ferromagnetic Phase ◽

Half Metallicity ◽

Heusler Compound

By using the first-principles calculations within the density functional theory (DFT), we investigate the structure, antiferromagnetic-ferromagnetic phase transition and half-metallicity of half-Heusler compound Fe1-XCuxMnSb. For the ferromagnetic state, the calculated lattice constant follows the Vegard law, and total ferromagnetic moment agrees with Slater-Pauling rule as x<0.5 while suffers large deviation as x>0.5. As x=0.75, a novel magnetic phase transition occurs, which mainly derives from the competition between RKKY and superexchange magnetic coupling. Further analyses on density of states (DOS) reveal that the Fermi level can be adjusted by doped Cu concentration in ferromagnetic state, and d partial DOS of Mn atoms with different spin orientation compensate for each other that results in symmetric spin-up and spin-down band in antiferromagnetic state.

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Erratum: “First-principles study of anomalous Nernst effect in half-metallic iron dichloride monolayer” [APL Mater. 8, 041105 (2020)]

APL Materials ◽

10.1063/5.0030714 ◽

2020 ◽

Vol 8 (11) ◽

pp. 119901

Author(s):

Rifky Syariati ◽

Susumu Minami ◽

Hikaru Sawahata ◽

Fumiyuki Ishii

Keyword(s):

First Principles ◽

Metallic Iron ◽

Nernst Effect ◽

Half Metallic ◽

First Principles Study ◽

Anomalous Nernst Effect

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Colossal anomalous Nernst effect in a correlated noncentrosymmetric kagome ferromagnet

Science Advances ◽

10.1126/sciadv.abf1467 ◽

2021 ◽

Vol 7 (13) ◽

pp. eabf1467

Author(s):

T. Asaba ◽

V. Ivanov ◽

S. M. Thomas ◽

S. Y. Savrasov ◽

J. D. Thompson ◽

...

Keyword(s):

Magnetic Field ◽

Electronic Structure ◽

Theoretical Calculations ◽

Zero Magnetic Field ◽

Nernst Effect ◽

Nodal Lines ◽

Transverse Response ◽

Narrow Bands ◽

Strong Spin ◽

Anomalous Nernst Effect

The transverse voltage generated by a temperature gradient in a perpendicularly applied magnetic field, termed the Nernst effect, has promise for thermoelectric applications and for probing electronic structure. In magnetic materials, an anomalous Nernst effect (ANE) is possible in a zero magnetic field. We report a colossal ANE in the ferromagnetic metal UCo0.8Ru0.2Al, reaching 23 microvolts per kelvin. Uranium’s 5f electrons provide strong electronic correlations that lead to narrow bands, a known route to producing a large thermoelectric response. In addition, uranium’s strong spin-orbit coupling produces an intrinsic transverse response in this material due to the Berry curvature associated with the relativistic electronic structure. Theoretical calculations show that in UCo0.8Ru0.2Al at least 148 Weyl nodes, and two nodal lines, exist within 60 millielectron volt of the Fermi level. This work demonstrates that magnetic actinide materials can host strong Nernst and Hall responses due to their combined correlated and topological nature.

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