Neutron scattering studies of the magnetic order in RNi{sub 2}B{sub 2}C

Journal Article · Sun Mar 31 23:00:00 EST 1996 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.362150· OSTI ID:282085

Lynn, J W; Huang, Q ^[1]; Sinha, S K ^[2]; Hossain, Z; Gupta, L C; Nagarajan, R ^[3]; Godart, C ^[4]

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1. Reactor Radiation Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899 (United States)
2. Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439 (United States)
3. Tata Institute of Fundamental Research, Bombay 400 005 (India)
4. CNRS, UPR-209, 92195 Meudon, Cedex (France)

Neutron diffraction was used to study magnetic order of RNi{sub 2}B{sub 2}C (R=Er, Ho, Dy). For Er the system orders antiferromagnetically at T{sub {ital N}}=6.8 K, and this long range order coexists with superconductivity (T{sub {ital c}}=11 K). The magnetic structure is an incommensurate, transversely polarized spin-density-wave state, with the modulation wave vector {delta} along the {ital a} axis and the moments along {ital b}. {delta} has a temperature-independent value of 0.5526 (2{pi}/{ital a}), with the structure squaring up at low temperatures. For R=Ho the moments also prefer to reside in the {ital a}{endash}{ital b} plane, but initially an incommensurate {ital c}-axis spiral state forms upon cooling, with {ital T}{sub {ital N}}{approx_equal}{ital T}{sub {ital C}}{approx_equal}8 K. This {ital c}-axis spiral consists of ferromagnetic sheets of Ho moments in the {ital a}{endash}{ital b} plane, but with each sheet rotated by 163{degree} as one proceeds along the {ital c} axis. Small {ital a}-axis peaks are also observed above the reentrant superconducting transition over a narrow temperature range, but the {ital c}-axis peaks dominate. Just below the reentrant transition at 5 K the magnetic system locks in to a simple commensurate antiferromagnetic structure, which permits superconductivity to be restored. The {ital c}-axis spiral, the {ital a}-axis component, the commensurate antiferromagnetic structure, and the superconducting phase are all in a delicate balance energetically, and this balance may be easily shifted by subtle changes in composition, magnetic field, and pressure. DyNi{sub 2}B{sub 2}C orders antiferromagnetically at {ital T}{sub {ital N}}=11 K, with the same commensurate antiferromagnetic structure as found for the holmium material at low temperature. The existence of superconductivity in some samples of DyNi{sub 2}B{sub 2}C is consistent with the antiferromagnetic structure observed. {copyright} {ital 1996 American Institute of Physics.}

• OSTI ID: 282085
• Report Number(s): CONF-951101--
• Journal Information: Journal of Applied Physics, Journal Name: Journal of Applied Physics Journal Issue: 8 Vol. 79; ISSN JAPIAU; ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
CRYSTAL-PHASE TRANSFORMATIONS
DYSPROSIUM BORIDES
DYSPROSIUM CARBIDES
ERBIUM BORIDES
ERBIUM CARBIDES
HOLMIUM BORIDES
HOLMIUM CARBIDES
MAGNETIC ORDERING
MAGNETIC PROPERTIES
MAGNETIC STRUCTURE
NEUTRON DIFFRACTION
NICKEL BORIDES
NICKEL CARBIDES
ORDER-DISORDER TRANSFORMATIONS
SPIN DENSITY WAVES
SUPERCONDUCTIVITY
TEMPERATURE DEPENDENCE
TEMPERATURE RANGE 0000-0013 K