講演題目：　Moderate lattice disorder and electronic ground state properties 
                               in U heavy fermion compounds

講　師　：　Dr. Stefan Sullow
　　　　　　　　　(Inst. fuer Metallphysik und Nukleare Festkoerperphysik
　　　　　　                    TU Braunschweig, Germany)
　　　　　　　　 
日　時　：　平成16年9月30日（木）　14:00-
場　所　：　北海道大学大学院理学研究科物理学専攻　大学院講義室
　　　　　　　理学部　2号館（2−11号室）

要　旨　：
　 　The interplay of disorder and electronic correlations represents a　central issue of the physics of strongly correlated electron systems(SCES). The properties of SCES are extraordinarily sensitive to small levels of crystallographic disorder. This is attributed to the electronic correlations, which enhance the effect of the disorder. Correspondingly, disorder has been proposed to greatly modify or control the physical properties of SCES in very many cases. However, a thorough understanding of this issue is still lacking. Here, I present a detailed discussion of the effects of moderate crystallgraphic disorder on ground state and electronic transport properties of uranium heavy fermion compounds. For this class of systems disorder effects are particularly prominent, causing highly unusual spin glass, short range ordered or Non-Fermi Liquid ground states. From an experimental point of view, the central tasks are to  determine the type and level of the disorder and to assess the influence of the disorder on the physical properties. I will address these questions within case studies on the U heavy fermion  systems URh₂Ge₂, UPt₂Si₂ and related compounds.

世話人　　　網塚　浩 （北海道大学大学院理学研究科）
　　　　　　　　　 (Tel: 011-706-3484、amiami@phys.sci.hokudai.ac.jp)