Research on quantum phase transition by a ferromagnetic fluctuation of ruthenates

2011 Fiscal Year Final Research Report

• Project/Area Number: 22760516
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Single-year Grants
• Research Field: Inorganic materials/Physical properties
• Research Institution: National Institute for Materials Science
• Principal Investigator: KIKUGAWA Naoki 独立行政法人物質・材料研究機構, 超伝導物性ユニット, 主任研究員 (00442731)
• Project Period (FY): 2010 – 2011
• Keywords: ルテニウム酸化物 / 不純物置換効果

Research Abstract

Layered perovskite ruthenates show a variety of novel physical properties, for instance, spin-triplet superconductivity and magnetism. In this study, we particularly focused on a bi-layered calcium-ruthenate, Ca_3Ru_2O_7, in order to clarify its fruitful phenomena originating from 4d degenerate t_<2g> orbitals. Surprisingly, we observed "metal-insulator transition" when we partly substitute nonmagnetic Ti^<4+> for Ru^<4+>. We also detected a novel magneto-transport property on this substituted system.

Research Products

• [Journal Article] Photoanodic properties of pulsed-laser-depositedτ-Fe2O3 electrode (2010)
  • Author(s): J. Cao, T. Kako, N. Kikugawa, J. H. Ye
  • Journal Title: Journal of Physics D-Applied Physics Volume: 43巻 Pages: 325101
  • Peer Reviewed
• [Journal Article] An orthophosphate semiconductor with photooxidation properties under visible-light irradiation (2010)
  • Author(s): Z. G. Yi, Zhiguo, J. H. Ye, N. Kikugawa, T. Kako, S. X. Ouyang, H. Stuart-Williams, H. Yang, J. Y. Cao, W. J. Luo, Z. S. Li, Y. Liu, R. L. Withers
  • Journal Title: Nature Materials Volume: 9巻 Pages: 559-564
  • Peer Reviewed
• [Journal Article] Quantum phase transitions in NbFe2 and Ca_3Ru_2O_7 (2010)
  • Author(s): W. J. Duncan, O. P. Welzel, D. Moroni-Klementowicz, C. Albrecht, P. G. Niklowitz, D. Gruner, M. Brando, A, Neubauer, C. Pfleiderer, N. Kikugawa, A. P. Mackenzie, F. M. Grosche
  • Journal Title: Physica Status Solidi B-Basic Solid State Physics Volume: 247巻 Pages: 544-548
  • Peer Reviewed
• [Presentation] 非磁性不純物置換したCa_3Ru_2O_7の金属-絶縁体転移 (2012)
  • Author(s): 菊川直樹,小玉恒太,土屋聡,寺嶋太一,宇治進也,前野悦輝
  • Organizer: 日本物理学会第67回年年次大会
  • Place of Presentation: 関西学院大学
  • Year and Date: 2012-03-27
• [Presentation] Ca_3Ru_2O_7の低キャリア性電子状態とその非磁性不純物効果 (2011)
  • Author(s): 菊川直樹,小玉恒太,土屋聡.宇治進也,前野悦輝, A. P. Mackenzie
  • Organizer: 日本物理学会2011年秋季大会
  • Place of Presentation: 富山大学
  • Year and Date: 2011-09-21
• [Presentation] Photo-induced oxidization properties of a silver orthophosphate under visible-light irradiation (2010)
  • Author(s): N. Kikugawa, Z. Yi, T. Kako, S. X. Ouyang, J. Cao, N. Umezawa, and J. H. Ye
  • Organizer: 4^<th> International Workshop on Advanced Ceramics
  • Place of Presentation: 名古屋工業大学
  • Year and Date: 2010-12-11