Magnetic excitations of NaxCoO2・yD2O: neutron scattering

• Moyoshi Taketo

  Department of Physics, Division of Material Science, Nagoya University

• Yasui Yukio

  Department of Physics, Division of Material Science, Nagoya University

• Kobayashi Yoshiaki

  Department of Physics, Division of Material Science, Nagoya University

• Sato Masatoshi

  Department of Physics, Division of Material Science, Nagoya University

• Kakurai Kazuhisa

  Quantum Beam Science Directorate, Japan Atomic Energy Agency

書誌事項

タイトル別名

• Magnetic Excitations of Na<I><SUB>x</SUB></I>CoO<SUB>2</SUB>·<I>y</I>D<SUB>2</SUB>O —Neutron Scattering—
• Magnetic Excitations of Na_<i>x</i>CoO₂·<i>y</i>D₂O –Neutron Scattering–

抄録

In neutron inelastic measurements on aligned crystals of Na_xCoO₂·yD₂O, two magnetic peaks have been observed. One peak corresponds to the contribution of ferromagnetic fluctuations and another peak, that of antiferromagnetic fluctuations. Both have two-dimensional characteristics. The intensity of ferromagnetic fluctuation decreases with decreasing temperature T and becomes inappreciable below 25 K. In contrast, antiferromagnetic fluctuation remains finite at 5 K. We have also carried out specific heat measurements on several samples with different values of the ⁵⁹Co-nuclear quadrupole frequency (ν_Q) within the region 12.0<ν_Q3≅3ν_Q<12.9 MHz, where the superconducting, nonsuperconducting and superconducting phases appear in the transition temperature (T_c)–ν_Q3 phase diagram with varying ν_Q3, and found that the electronic specific heat coefficient γ does not change so significantly as to indicate a topological change of the Fermi surface with ν_Q. These results imply that hole pockets, the existence of which is suggested by band calculations near the K points in the reciprocal space, do not exist in the entire superconducting ν_Q3 region and support that the superconducting pair symmetry does not change with ν_Q3 in the phase diagram.

収録刊行物

• Ｊｏｕｒｎａｌ　ｏｆ　ｔｈｅ　Ｐｈｙｓｉｃａｌ　Ｓｏｃｉｅｔｙ　ｏｆ　Ｊａｐａｎ

  Ｊｏｕｒｎａｌ　ｏｆ　ｔｈｅ　Ｐｈｙｓｉｃａｌ　Ｓｏｃｉｅｔｙ　ｏｆ　Ｊａｐａｎ 77 (7), 073709-073709, 2008

  一般社団法人 日本物理学会

キーワード

• Na<I><SUB>x</SUB></I>CoO<SUB>2</SUB>·<I>y</I>D<SUB>2</SUB>O
• Na<I><SUB>x</SUB></I>CoO<SUB>2</SUB>
• neutron scattering
• magnetic excitations

詳細情報

• CRID: 1390001204197736320
• NII論文ID: 130005436513
• NII論文ID: 110006821290
• NII論文ID: 210000107310
• NII書誌ID: AA00704814
• DOI: 10.1143/jpsj.77.073709
• ISSN: 13474073
• ISSN: 00319015
• NDL書誌ID: 9576808
• Web Site: https://ndlsearch.ndl.go.jp/books/R000000004-I9576808
• Web Site: http://journals.jps.jp/doi/pdf/10.1143/JPSJ.77.073709
• 本文言語コード: en
• データソース種別:
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