start-ver=1.4 cd-journal=joma no-vol=81 cd-vols= no-issue=5 article-no= start-page=053701-1 end-page=053701-4 dt-received= dt-revised= dt-accepted= dt-pub-year=2012 dt-pub=20120406 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Superconductivity Induced by Bond Breaking in the Triangular Lattice of IrTe2 en-subtitle= kn-subtitle= en-abstract= kn-abstract=IrTe2, a layered compound with a triangular iridium lattice, exhibits a structural phase transition at approximately 250 K. This transition is characterized by the formation of Ir-Ir bonds along the b-axis. We found that the breaking of Ir-Ir bonds that occurs in Ir1-xPtxTe2 results in the appearance of a structural critical point in the T = 0 limit at x(c) similar or equal to 0.035. Although both IrTe2 and PtTe2 are paramagnetic metals, superconductivity at T-c = 3.1 K is induced by the bond breaking in a narrow range of x >= x(c) in Ir1-xPtxTe2. This result indicates that structural fluctuations can be involved in the emergence of superconductivity. en-copyright= kn-copyright= en-aut-name=PyonSunseng en-aut-sei=Pyon en-aut-mei=Sunseng kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=KudoKazutaka en-aut-sei=Kudo en-aut-mei=Kazutaka kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=NoharaMinoru en-aut-sei=Nohara en-aut-mei=Minoru kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= affil-num=1 en-affil= kn-affil=Department of Physics, Faculty of Science, Okayama University affil-num=2 en-affil= kn-affil=Department of Physics, Faculty of Science, Okayama University affil-num=3 en-affil= kn-affil=Department of Physics, Faculty of Science, Okayama University en-keyword=superconductivity kn-keyword=superconductivity en-keyword=IrTe2 kn-keyword=IrTe2 en-keyword=Pt doping kn-keyword=Pt doping en-keyword=triangular lattice kn-keyword=triangular lattice en-keyword=phase diagram kn-keyword=phase diagram en-keyword=structural phase transition kn-keyword=structural phase transition END start-ver=1.4 cd-journal=joma no-vol=79 cd-vols= no-issue=12 article-no= start-page=124701-1 end-page=124701-4 dt-received= dt-revised= dt-accepted= dt-pub-year=2010 dt-pub=20101125 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Electronic Structure of the Novel Filled Skutterudite PrPt4Ge12 Superconductor en-subtitle= kn-subtitle= en-abstract= kn-abstract=We have performed soft x-ray photoemission spectroscopy (SXPES) and resonant photoemission spectroscopy (RPES) of the filled skutterudite superconductor PrPt4Ge12 in order to study the electronic structure of valence band and the character of Pr 4f. SXPES of PrPt4Ge12 measured with 1200 eV photon energy, where spectral contribution of Pr 4f is negligible, was found nearly identical with that of LaPt4Ge12, indicating similarity of Pt–Ge derived electronic states of the two compounds. Good correspondence with band calculations allows us to ascribe the dominant Ge 4p character of the density of states at the Fermi level (EF). Pr 3d → 4f RPES shows that, although Pr 4f electrons in PrPt4Ge12 are not as strongly hybridized with conduction electrons near EF as in PrFe4P12, there are finite Pr 4f contribution to the states near EF in PrPt4Ge12. These PES results give the information of fundamental electronic structure for understanding the physical properties of the novel filled skutterudite superconductor PrPt4Ge12. en-copyright= kn-copyright= en-aut-name=NakamuraYoshiaki en-aut-sei=Nakamura en-aut-mei=Yoshiaki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=OkazakiHiroyuki en-aut-sei=Okazaki en-aut-mei=Hiroyuki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=YoshidaRikiya en-aut-sei=Yoshida en-aut-mei=Rikiya kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= en-aut-name=WakitaTakanori en-aut-sei=Wakita en-aut-mei=Takanori kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=4 ORCID= en-aut-name=HiraiMasaaki en-aut-sei=Hirai en-aut-mei=Masaaki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=5 ORCID= en-aut-name=MuraokaYuji en-aut-sei=Muraoka en-aut-mei=Yuji kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=6 ORCID= en-aut-name=TakeyaHiroyuki en-aut-sei=Takeya en-aut-mei=Hiroyuki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=7 ORCID= en-aut-name=HirataKazuto en-aut-sei=Hirata en-aut-mei=Kazuto kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=8 ORCID= en-aut-name=KumigashiraHiroshi en-aut-sei=Kumigashira en-aut-mei=Hiroshi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=9 ORCID= en-aut-name=OshimaMasaharu en-aut-sei=Oshima en-aut-mei=Masaharu kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=10 ORCID= en-aut-name=YokoyaTakayoshi en-aut-sei=Yokoya en-aut-mei=Takayoshi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=11 ORCID= affil-num=1 en-affil= kn-affil=The Graduate School of Science and Technology, Okayama University affil-num=2 en-affil= kn-affil=The Graduate School of Science and Technology, Okayama University affil-num=3 en-affil= kn-affil=The Graduate School of Science and Technology, Okayama University affil-num=4 en-affil= kn-affil=The Graduate School of Science and Technology, Okayama University affil-num=5 en-affil= kn-affil=The Graduate School of Science and Technology, Okayama University affil-num=6 en-affil= kn-affil=The Graduate School of Science and Technology, Okayama University affil-num=7 en-affil= kn-affil=National Institute for Materials Science (NIMS) affil-num=8 en-affil= kn-affil=National Institute for Materials Science (NIMS) affil-num=9 en-affil= kn-affil=CREST, Japan Science and Technology Corporation (JST) affil-num=10 en-affil= kn-affil=CREST, Japan Science and Technology Corporation (JST) affil-num=11 en-affil= kn-affil=The Graduate School of Science and Technology, Okayama University en-keyword=PrPt4Ge12 kn-keyword=PrPt4Ge12 en-keyword=filled skutterudite kn-keyword=filled skutterudite en-keyword=superconductor kn-keyword=superconductor en-keyword=soft x-ray photoemission spectroscopy kn-keyword=soft x-ray photoemission spectroscopy en-keyword=Pr 3d → 4f resonant photoemission kn-keyword=Pr 3d → 4f resonant photoemission en-keyword=electronic structure kn-keyword=electronic structure END