Anisotropy of Spin Fluctuations in a Tetragonal Heavy Fermion Antiferromagnet CeRhAl4Si2

[摘要] An antiferromagnetic (AFM) Kondo lattice compound CeRhAl4Si2, which exhibits successive AFM transitions at TN1=14 K and TN2=9 K in zero external field, has been microscopically investigated by means of27Al nuclear magnetic resonance (NMR) technique. In the high temperature range, magnetic excitations of 4f electrons can be well explained by isotropic localized spin fluctuations. Below ∼50 K, it begins to show a characteristic anisotropy of spin fluctuations, which suggests a competition between spin fluctuations and nesting instability in this system.

[发布机构] Advanced Science Research Center, Japan Atomic Energy Agency, Ibaraki, Tokai; 319-1195, Japan^1;Condensed Matter and Magnet Science, Los Alamos National Laboratory, Los Alamos; NM; 87545, United States^2;Materials Science Division, Argonne National Laboratory, Argonne; IL; 60439, United States^3

[关键词] Antiferromagnetics;Antiferromagnets;External fields;Heavy fermion;High temperature range;Kondo lattices;Magnetic excitations;Nuclear magnetic resonance techniques