Generalized theory of spin fluctuations in itinerant electron magnets: Crucial role of spin anharmonicity

JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS

卷:383

Article; Proceedings Paper

Solontsov, A.^1,2 

[1] NL Dukhov Res Inst Automat, Ctr Fundamental & Appl Res, Moscow 127055, Russia

[2] State Ctr Condensed Matter Phys, Moscow 115569, Russia

关键词: Itinerant electron magnetism;    Spin fluctuations;    Zero-point effects;    Spin anharmonicity;    Specific heat;    Half-metallic ferromagnets;   

DOI  :  10.1016/j.jmmm.2014.11.023

来源: Elsevier

【 摘 要 】

The paper critically overviews the recent developments of the theory of spatially dispersive spin fluctuations (SF) in itinerant electron magnetism with particular emphasis on spin-fluctuation coupling or spin anharmonicity. It is argued that the conventional self-consistent renormalized (SCR) theory of spin fluctuations is usually used aside of the range of its applicability actually defined by the constraint of weak spin anharmonicity based on the random phase approximation (RPA) arguments. An essential step in understanding SF in itinerant magnets beyond RPA-like arguments was made recently within the soft-mode theory of SF accounting for strong spin anharmonicity caused by zero-point SF. In the present paper we generalize it to apply for a wider range of temperatures and regimes of SF and show it to lead to qualitatively new results caused by zero-point effects. (C) 2015 Elsevier B.V. All rights reserved.

【 授权许可】

Free