Magnetic field‐dependent spin structures of nanocrystalline holmium. Issue 2 (18th March 2016)

• Record Type: Journal Article
• Authors: Szary, Philipp; Kaiser, Daniel; Bick, Jens-Peter; Lott, Dieter; Heinemann, André; Dewhurst, Charles; Birringer, Rainer; Michels, Andreas
• Is Part Of: Journal of applied crystallography. Volume 49:Issue 2(2016)
• Page Start: 533
• Page End: 538
• Publication Date: 2016-03-18
• Subjects: neutron diffraction -- spin structures -- rare earth metals -- magnetic materials -- nanocrystalline holmium; Crystallography -- Periodicals; 548.05
• DOI: 10.1107/S1600576716001898
• Languages: English
• ISSNs: 0021-8898

Abstract

Abstract : Neutron diffraction experiments on nanocrystalline holmium suggest the absence of helifan(3/2) and helifan(2) structures at 50 K. Abstract : 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.