Finite-size effect on magnetic ordering temperatures in long-period antiferromagnets: Holmium thin films

• Published in: Physical review letters 2004-10, Vol.93 (15), p.157204.1-157204.4, Article 157204
• Main Authors: WESCHKE, E, OTT, H, JENSEN, P. J, SCHIERLE, E, SCHÜSSLER-LANGEHEINE, C, VYALIKH, D. V, KAINDL, G, LEINER, V, AY, M, SCHMITTE, T, ZABEL, H
• Format: Article
• Language: English
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Exact sciences and technology; Magnetic properties and materials; Magnetic properties of monolayers and thin films; Magnetic properties of surface, thin films and multilayers; Physics; Spin arrangements in magnetically ordered materials (including neutron and spin-polarized electron studies, synchrotron-source x-ray scattering, etc.)
• ISSN: 0031-9007; 1079-7114
• DOI: 10.1103/physrevlett.93.157204

The thickness dependence of the helical antiferromagnetic ordering temperature T(N) was studied for thin Ho metal films by resonant magnetic soft x-ray and neutron diffraction. In contrast with the Curie temperature of ferromagnets, T(N) was found to decrease with film thickness d according to [T(N)(infinity)-T(N)(d)]/T(N)(d) proportional variant (d-d(0))(-lambda(')), where lambda(') is a phenomenological exponent and d(0) is of the order of the bulk magnetic period L(b). These observations are reproduced by mean-field calculations that suggest a linear relationship between d(0) and L(b) in long-period antiferromagnets.