Magnetic phase transitions and entropy change in layered NdMn{sub 1.7}Cr{sub 0.3}Si{sub 2}

Journal Article · Mon Jan 27 00:00:00 EST 2014 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.4863230· OSTI ID:22280573

Dou, S. X. ^[1]; Wang, J. L. ^[1]; Campbell, S. J. ^[2]; Studer, A. J.; Avdeev, M.; Kennedy, S. J. ^[3]; Gu, Q. F. ^[4]; Zeng, R. ^[1]

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1. Institute for Superconductivity and Electronic Materials, University of Wollongong, Wollongong, New South Wales 2522 (Australia)
2. School of Physical, Environmental, and Mathematical Sciences, The University of New South Wales, Canberra, The Australian Defence Force Academy, Australian Capital Territory 2600 (Australia)
3. Bragg Institute, Australian Nuclear Science and Technology Organization, Lucas Heights, New South Wales 2234 (Australia)
4. Australian Synchrotron, 800 Blackburn Rd, Clayton 3168 (Australia)

A giant magnetocaloric effect has been observed around the Curie temperature, T{sub C} ∼ 42 K, in NdMn{sub 1.7}Cr{sub 0.3}Si{sub 2} with no discernible thermal and magnetic hysteresis losses. Below 400 K, three magnetic phase transitions take place around 380 K, 320 K and 42 K. Detailed high resolution synchrotron and neutron powder diffraction (10–400 K) confirmed the magnetic transitions and phases as follows: T{sub N}{sup intra} ∼ 380 K denotes the transition from paramagnetism to intralayer antiferromagnetism (AFl), T{sub N}{sup inter} ∼ 320 K represents the transition from the AFl structure to the canted antiferromagnetic spin structure (AFmc), while T{sub C} ∼ 42 K denotes the first order magnetic transition from AFmc to canted ferromagnetism (Fmc + F(Nd)) due to ordering of the Mn and Nd sub-lattices. The maximum values of the magnetic entropy change and the adiabatic temperature change, around T{sub C} for a field change of 5 T are evaluated to be −ΔS{sub M}{sup max} ∼ 15.9 J kg{sup −1} K{sup −1} and ΔT{sub ad}{sup max} ∼ 5 K, respectively. The first order magnetic transition associated with the low levels of hysteresis losses (thermal <∼0.8 K; magnetic field <∼0.1 T) in NdMn{sub 1.7}Cr{sub 0.3}Si{sub 2} offers potential as a candidate for magnetic refrigerator applications in the temperature region below 45 K.

• OSTI ID: 22280573
• Journal Information: Applied Physics Letters, Vol. 104, Issue 4; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ANTIFERROMAGNETISM
CHROMIUM SILICIDES
CURIE POINT
ENTROPY
FERROMAGNETISM
HYSTERESIS
MAGNETIC FIELDS
MAGNETIC PROPERTIES
MAGNETIC REFRIGERATORS
MANGANESE COMPOUNDS
NEODYMIUM COMPOUNDS
NEUTRON DIFFRACTION
PARAMAGNETISM
PHASE TRANSFORMATIONS
SPIN
TEMPERATURE DEPENDENCE