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Title: Giant field-induced adiabatic temperature changes in In-based off-stoichiometric Heusler alloys

Authors:
 [1];  [1];  [1];  [1]; ORCiD logo [2];  [2];  [2];  [1];  [2];  [3];  [1]
  1. Department of Physics, Southern Illinois University, Carbondale, Illinois 62901, USA
  2. Faculty of Physics, Lomonosov Moscow State University, Moscow 119991, Russia
  3. Department of Physics and Astronomy, Louisiana State University, Baton Rouge, Louisiana 70803, USA
Publication Date:
Sponsoring Org.:
USDOE
OSTI Identifier:
1361802
Grant/Contract Number:
FG02-06ER46291; FG02-13ER46946
Resource Type:
Journal Article: Publisher's Accepted Manuscript
Journal Name:
Journal of Applied Physics
Additional Journal Information:
Journal Volume: 121; Journal Issue: 13; Related Information: CHORUS Timestamp: 2018-02-14 20:22:37; Journal ID: ISSN 0021-8979
Publisher:
American Institute of Physics
Country of Publication:
United States
Language:
English

Citation Formats

Pandey, Sudip, Quetz, Abdiel, Aryal, Anil, Dubenko, Igor, Blinov, Mikhail, Rodionov, Igor, Prudnikov, Valerii, Mazumdar, Dipanjan, Granovsky, Alexander, Stadler, Shane, and Ali, Naushad. Giant field-induced adiabatic temperature changes in In-based off-stoichiometric Heusler alloys. United States: N. p., 2017. Web. doi:10.1063/1.4979475.
Pandey, Sudip, Quetz, Abdiel, Aryal, Anil, Dubenko, Igor, Blinov, Mikhail, Rodionov, Igor, Prudnikov, Valerii, Mazumdar, Dipanjan, Granovsky, Alexander, Stadler, Shane, & Ali, Naushad. Giant field-induced adiabatic temperature changes in In-based off-stoichiometric Heusler alloys. United States. doi:10.1063/1.4979475.
Pandey, Sudip, Quetz, Abdiel, Aryal, Anil, Dubenko, Igor, Blinov, Mikhail, Rodionov, Igor, Prudnikov, Valerii, Mazumdar, Dipanjan, Granovsky, Alexander, Stadler, Shane, and Ali, Naushad. Fri . "Giant field-induced adiabatic temperature changes in In-based off-stoichiometric Heusler alloys". United States. doi:10.1063/1.4979475.
@article{osti_1361802,
title = {Giant field-induced adiabatic temperature changes in In-based off-stoichiometric Heusler alloys},
author = {Pandey, Sudip and Quetz, Abdiel and Aryal, Anil and Dubenko, Igor and Blinov, Mikhail and Rodionov, Igor and Prudnikov, Valerii and Mazumdar, Dipanjan and Granovsky, Alexander and Stadler, Shane and Ali, Naushad},
abstractNote = {},
doi = {10.1063/1.4979475},
journal = {Journal of Applied Physics},
number = 13,
volume = 121,
place = {United States},
year = {Fri Apr 07 00:00:00 EDT 2017},
month = {Fri Apr 07 00:00:00 EDT 2017}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record at 10.1063/1.4979475

Citation Metrics:
Cited by: 3works
Citation information provided by
Web of Science

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  • The characteristic rich shifting of the maximum adiabatic flame temperature from the stoichiometric value for mixtures of hydrocarbon and air is demonstrated to be caused by product dissociation and hence reduced amount of heat release. Since the extent of dissociation is greater on the lean side as a result of the stoichiometry of dissociated products, the peaking occurs on the rich side. The specific heat per unit mass of the mixture is shown to increase monotonically with increasing fuel concentration, and as such tends to shift the peak toward the lean side. It is further shown that this is themore » cause for the lean shifting of the adiabatic flame temperature of oxidizer-enriched mixtures of N{sub m}H{sub n} and F{sub 2} and of NH{sub 3} and O{sub 2}, with various amounts of inert dilution, even though their maximum heat release still peaks on the rich side. (author)« less
  • The properties of Co{sub 2}(Mn{sub 1−x}Fe{sub x})Ge (CMFG) (x = 0–0.4) Heusler alloy magnetic layers within polycrystalline current-perpendicular-to-the plane giant magnetoresistance (CPP-GMR) spin-valves are investigated. CMFG films annealed at 220–320 °C exhibit partly ordered B2 structure with an order parameter S{sub B2} = 0.3–0.4, and a lower S{sub B2} was found for a higher Fe content. Nevertheless, CPP-GMR spin-valve devices exhibit a relatively high magnetoresistance ratio of ∼13% and a magnetoresistance-area product (ΔRA) of ∼6 mΩ μm{sup 2} at room temperature, which is almost independent of the Fe content in the CMFG films. By contrast, at low temperatures, ΔRA clearly increases with higher Fe content,more » despite the lower B2 ordering for increasing the Fe content. Indeed, first-principles calculations reveal that the CMFG alloy with a partially disordered B2 structure has a greater density of d-state at the Fermi level in the minority band compared to the Fe-free (Co{sub 2}MnGe) alloy. This could explain the larger ΔRA measured on CMFG at low temperatures by assuming that s-d scattering mainly determines the spin asymmetry of resistivity as described in Mott's theory.« less
  • We perform a combined theoretical and experimental study of the phase stability and magnetism of the off-stoichiometric Ni{sub 1-x}Mn{sub 1+x}Sb in the half-Heusler crystal phase. Our work is motivated by the need for strategies to engineer the magnetism of potentially half-metallic materials, such as NiMnSb, for improved performance at elevated temperatures. By means of ab initio calculations we investigate Ni{sub 1-x}Mn{sub 1+x}Sb over the whole composition range 0{<=}x{<=}1 of Ni replacing Mn and show that at relevant temperatures, the half-Heusler phase should be thermodynamically stable up to at least x=0.20 with respect to the competing C38 structure of Mn{sub 2}Sb.more » Furthermore we find that half-Heusler Ni{sub 1-x}Mn{sub 1+x}Sb retains half-metallic band structure over the whole concentration range and that the magnetic moments of substitutional Mn{sub Ni} atoms display magnetic exchange interactions an order of magnitude larger than the Ni-Mn interaction in NiMnSb. We also demonstrate experimentally that the alloys indeed can be created by synthesizing off-stoichiometric Ni{sub 1-x}Mn{sub 1+x}Sb films on MgO substrates by means of magnetron sputtering.« less
  • The thermoelectric properties of Heusler-type Fe{sub 2−x}V{sub 1+x}Al{sub 1−y}Si{sub y} and Fe{sub 2−x}V{sub 1+x−y}Ti{sub y}Al alloys have been investigated to clarify which off-stoichiometric alloy, i.e., V-rich (x > 0) or V-poor (x < 0), is more effective in enhancing the Seebeck coefficient when doped by Si and Ti, while retaining a low electrical resistivity. Large Seebeck coefficients of −182 μV/K and 110 μV/K at 300 K are obtained for n-type Fe{sub 1.95}V{sub 1.05}Al{sub 0.97}Si{sub 0.03} and p-type Fe{sub 2.04}V{sub 0.93}Ti{sub 0.03}Al, respectively. When the Seebeck coefficient is plotted as a function of valence electron concentration (VEC), the VEC dependence for the doped off-stoichiometric alloys falls on characteristicmore » curves depending on the off-stoichiometric composition x. It is concluded that a larger Seebeck coefficient with a negative sign can be obtained for the V-rich alloys rather than the V-poor alloys, whilst good p-type materials are always derived from the V-poor alloys. Substantial enhancements in the Seebeck coefficient for the off-stoichiometric alloys could be achieved by a favorable modification in the electronic structure around the Fermi level through the antisite V or Fe defect formation.« less