Magnetic field-dependent spin structures of nanocrystalline holmium

Autor: Daniel Kaiser, Jens-Peter Bick, D. Lott, Andreas Michels, Charles Dewhurst, A. Heinemann, Philipp Szary, Rainer Birringer
Jazyk: angličtina
Rok vydání: 2016
Předmět:
Zdroj: 'Journal of Applied Crystallography ', vol: 49, pages: 533-538 (2016)
Journal of Applied Crystallography
Szary, P.; Kaiser, D.; Bick, J.-P.; Lott, D.; Heinemann, A.; Dewhurst, C.; Birringer, R.; Michels, A.: Magnetic field-dependent spin structures of nanocrystalline holmium. In: Journal of Applied Crystallography. Vol. 49 (2016) 533-538. (DOI: /10.1107/S1600576716001898)
ISSN: 0021-8898
Popis: Neutron diffraction experiments on nanocrystalline holmium suggest the absence of helifan(3/2) and helifan(2) structures at 50 K.
The results are reported of magnetic field-dependent neutron diffraction experiments on polycrystalline inert-gas condensed holmium with a nanometre crystallite size (D = 33 nm). At T = 50 K, no evidence is found for the existence of helifan(3/2) or helifan(2) structures for the nanocrystalline sample, in contrast with results reported in the literature for the single crystal. Instead, when the applied field H is increased, the helix pattern transforms progressively, most likely into a fan structure. It is the component of H which acts on the basal-plane spins of a given nanocrystallite that drives the disappearance of the helix; for nanocrystalline Ho, this field is about 1.3 T, and it is related to a characteristic kink in the virgin magnetization curve. For a coarse-grained Ho sample, concomitant with the destruction of the helix phase, the emergence of an unusual angular anisotropy (streak pattern) and the appearance of novel spin structures are observed.
Databáze: OpenAIRE