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Title: Phase transitions and magnetocaloric and transport properties in off-stoichiometric GdNi2Mnx

Authors:
 [1];  [1];  [1];  [2];  [1];  [1];  [2];  [1]
  1. Department of Physics, Southern Illinois University, Carbondale, Illinois 62901, USA
  2. Department of Physics and Astronomy, Louisiana State University, Baton Rouge, Louisiana 70803, USA
Publication Date:
Sponsoring Org.:
USDOE
OSTI Identifier:
1236398
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: 119; Journal Issue: 4; Related Information: CHORUS Timestamp: 2018-03-29 14:17:54; Journal ID: ISSN 0021-8979
Publisher:
American Institute of Physics
Country of Publication:
United States
Language:
English

Citation Formats

Aryal, Anil, Quetz, Abdiel, Pandey, Sudip, Samanta, Tapas, Dubenko, Igor, Mazumdar, Dipanjan, Stadler, Shane, and Ali, Naushad. Phase transitions and magnetocaloric and transport properties in off-stoichiometric GdNi2Mnx. United States: N. p., 2016. Web. doi:10.1063/1.4940877.
Aryal, Anil, Quetz, Abdiel, Pandey, Sudip, Samanta, Tapas, Dubenko, Igor, Mazumdar, Dipanjan, Stadler, Shane, & Ali, Naushad. Phase transitions and magnetocaloric and transport properties in off-stoichiometric GdNi2Mnx. United States. doi:10.1063/1.4940877.
Aryal, Anil, Quetz, Abdiel, Pandey, Sudip, Samanta, Tapas, Dubenko, Igor, Mazumdar, Dipanjan, Stadler, Shane, and Ali, Naushad. Thu . "Phase transitions and magnetocaloric and transport properties in off-stoichiometric GdNi2Mnx". United States. doi:10.1063/1.4940877.
@article{osti_1236398,
title = {Phase transitions and magnetocaloric and transport properties in off-stoichiometric GdNi2Mnx},
author = {Aryal, Anil and Quetz, Abdiel and Pandey, Sudip and Samanta, Tapas and Dubenko, Igor and Mazumdar, Dipanjan and Stadler, Shane and Ali, Naushad},
abstractNote = {},
doi = {10.1063/1.4940877},
journal = {Journal of Applied Physics},
number = 4,
volume = 119,
place = {United States},
year = {Thu Jan 28 00:00:00 EST 2016},
month = {Thu Jan 28 00:00:00 EST 2016}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record at 10.1063/1.4940877

Citation Metrics:
Cited by: 6works
Citation information provided by
Web of Science

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  • The structural, magnetic, magnetocaloric, transport, and magnetoresistance properties of the rare-earth intermetallic compounds GdNi{sub 2}Mn{sub x} (0.5 ≤ x ≤ 1.5) have been studied. The compounds with x = 0.5 and 0.6 crystallize in the cubic MgCu{sub 2} type phase, whereas samples with x ≥ 0.8 form a mixed MgCu{sub 2} and rhombohedral PuNi{sub 3} phase. A second order magnetic phase transition from a ferromagnetic to paramagnetic state was observed near the Curie temperature (T{sub C}). The GdNi{sub 2}Mn{sub x} (0.5 ≤ x ≤ 1.5) compounds order in a ferrimagnetic structure in the ground state. The largest observed values of magnetic entropy changes (at T{sub C} for ΔH = 5T) were 3.9, 3.5, andmore » 3.1 J/kg K for x = 0.5, 0.6, and 0.8, respectively. The respective relative values of the cooling power were 395, 483, and 220 J/kg. These values are greater than some well-known prototype magnetocaloric materials such as Gd (400 J/kg) and Gd{sub 5}Si{sub 2}Ge{sub 2} (240 J/kg). Analysis of the resistivity data showed a T{sup 2} dependence at low temperatures, suggesting strong electron-phonon interactions, whereas at higher temperatures s-d scattering was dominated by the electron-phonon contribution, resulting in a slow increase in resistivity. Magnetoresistance values of ∼−1.1% were found for x = 0.5 near T{sub C}, and −7% for x = 1.5 near T = 80 K.« less
  • Tmore » he structural, magnetic, and magnetocaloric properties of MnC o 1 - x Z r x Ge ( 0.01 x 0.04 ) have been studied through X-ray diffraction, differential scanning calorimetry, and magnetization measurements. Results indicate that the partial substitution of Zr for Co in MnC o 1 - x Z r x Ge decreases the martensitic transition temperature ( M ). For x = 0.02, M was found to coincide with the ferromagnetic transition temperature ( C ) resulting in a first-order magnetostructural transition (MS). A further increase in zirconium concentration ( x = 0.04) showed a single transition at C . he MS from the paramagnetic to ferromagnetic state results in magnetic entropy changes ( - Δ S M ) of 7.2 J/kgK for Δ H = 5 at 274 K for x = 0.02. he corresponding value of the relative cooling power (RCP) was found to be 266 J/kg for Δ H = 5 . hus, the observed large value of MCE and RCP makes this system a promising material for magnetic cooling applications.« less
  • Tmore » he structural, magnetic, and magnetocaloric properties of MnC o 1 - x Z r x Ge ( 0.01 x 0.04 ) have been studied through X-ray diffraction, differential scanning calorimetry, and magnetization measurements. Results indicate that the partial substitution of Zr for Co in MnC o 1 - x Z r x Ge decreases the martensitic transition temperature ( M ). For x = 0.02, M was found to coincide with the ferromagnetic transition temperature ( C ) resulting in a first-order magnetostructural transition (MS). A further increase in zirconium concentration ( x = 0.04) showed a single transition at C . he MS from the paramagnetic to ferromagnetic state results in magnetic entropy changes ( - Δ S M ) of 7.2 J/kgK for Δ H = 5 at 274 K for x = 0.02. he corresponding value of the relative cooling power (RCP) was found to be 266 J/kg for Δ H = 5 . hus, the observed large value of MCE and RCP makes this system a promising material for magnetic cooling applications.« less
  • AgSbTe{sub 2} is a thermoelectric semiconductor with an intrinsically low thermal conductivity and a valence band structure that is favorable to obtaining a high thermoelectric figure of merit zT. It also has a very small energy gap Eg ∼ 7.6 ± 3 meV. As this gap is less than the thermal excitation energy at room temperature, near-intrinsic AgSbTe{sub 2} is a two carrier system having both holes (concentration p) and electrons (n). Good thermoelectric performance requires heavy p-type doping (p > > n). This can be achieved with native defects or with extrinsic doping, e.g. with transition metal element. Themore » use of defect doping is complicated by the fact that many of the ternary Ag-Sb-Te and pseudo-binary Sb{sub 2}Te{sub 3}-Ag{sub 2}Te phase diagrams are contradictory. This paper determines the compositional region most favorable to creating a single phase material. Through a combination of intrinsic and extrinsic doping, values of zT > 1 are achieved, though not on single-phased material. Additionally, we show that thermal conductivity is not affected by defects, further demonstrating that the low lattice thermal conductivity of I-V-VI{sub 2} materials is due to an intrinsic mechanism, insensitive to changes in defect structure.« less