1999/10/31 by M. Hennion, F. Moussa, J. Rodriguez-Carvajal +4 · 2 citations
Materials Science · Physics and Astronomy · #Advanced Condensed Matter Physics #Magnetic and transport properties of perovskites and related materials #Rare-earth and actinide compounds #cond-mat.str-el
paper · pdf · doi:10.1103/physrevb.61.9513
published as Physical Review B Volume 61, Number 13, 1 April 2000 · 11 pages, 11 figures
arxiv created 2000/02/29 · openalex publication_date 2000/04/01 · arxiv updated 2009/11/30 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
Elastic and inelastic neutron-scattering experiments have been performed in a La0.94Sr0.06MnO3 untwinned crystal, which exhibits an antiferromagnetic canted magnetic structure with ferromagnetic layers. The elastic small q scattering exhibits a modulation with an anisotropic q dependence. It can be pictured by ferromagnetic inhomogeneities or large magnetic polarons with a platelike shape, the largest size (\ensuremath≈17 \AA) and largest interpolaron distance (\ensuremath≈38 \AA) being within the ferromagnetic layers. Comparison with observations performed on Ca-doped samples, which show the growth of the magnetic polarons with doping, suggests that this growth is faster for the Sr than for the Ca substitution. Below the gap of the spin-wave branch typical of the antiferromagnetic layered magnetic structure, an additional spin-wave branch reveals a ferromagnetic and isotropic coupling, already found in Ca-doped samples. Its q-dependent intensity, very anisotropic, closely reflects the ferromagnetic correlations found for the static clusters. All these results agree with a two-phase electronic segregation occurring on a very small scale, although some characteristics of a canted state are also observed suggesting a weakly inhomogeneous state.