2001/10/31 by Shinji Watanabe, Kazumasa Miyake · 3 citations
Materials Science · Physics and Astronomy · #Iron-based superconductors research #Physics of Superconductivity and Magnetism #Rare-earth and actinide compounds #cond-mat.str-el #cond-mat.supr-con
paper · pdf · doi:10.1143/jpsj.71.2489
published as J. Phys. Soc. Jpn. 71 (2002) 2489-2499 · (12 pages, 10 eps figures) submitted to J. Phys. Soc. Jpn
arxiv created 2002/05/02 · openalex publication_date 2002/10/15 · arxiv updated 2009/11/30 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
It is shown that anomalous properties of UGe2 can be understood in a unified way on the basis of a single assumption that the superconductivity is mediated by the coupled SDW and CDW fluctuations induced by the imperfect nesting of the Fermi surface with majority spins at T=Tx(P) deep in the ferromagnetic phase. Excess growth of uniform magnetization is shown to develop in the temperature range T<Tx(P) as a mode-coupling effect of coupled growth of SDW and CDW orderings, which has been observed by two different types of experiments. The coupled CDW and SDW fluctuations are shown to be essentially ferromagnetic spin fluctuations which induce a spin-triplet p-wave attraction. These fluctuations consist of two modes, spin and charge fluctuations with large momentum transfer of the nesting vector. An anomalous temperature dependence of the upper critical field Hc2(T) such as crossing of Hc2(T) at P=11.4 kbar and P=13.5 kbar, can be understood by the strong-coupling-superconductivity formalism. Temperature dependence of the lattice specific heat including a large shoulder near Tx is also explained quite well as an effect of a kind of Kohn anomaly associated with coupled SDW-CDW transition.