Masatoshi Imada

Publications (2)1.78 Total impact

• Source

  Available from: arxiv.org

  Article: Superconductivity emerging near quantum critical point of valence transition

  Shinji Watanabe, Masatoshi Imada, Kazumasa Miyake
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  ABSTRACT: The nature of the quantum valence transition is studied in the one-dimensional periodic Anderson model with Coulomb repulsion between f and conduction electrons by the density-matrix renormalization group method. It is found that the first-order valence transition emerges with the quantum critical point and the crossover from the Kondo to the mixed-valence states is strongly stabilized by quantum fluctuation and electron correlation. It is found that the superconducting correlation is developed in the Kondo regime near the sharp valence increase. The origin of the superconductivity is ascribed to the development of the coherent motion of electrons with enhanced valence fluctuation, which results in the enhancement of the charge velocity, but not of the charge compressibility. Statements on the valence transition in connection with Ce metal and Ce compounds are given.
  03/2006;
• Article: Quantum valence criticality and superconductivity

  Shinji Watanabe, Masatoshi Imada, Kazumasa Miyake
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  ABSTRACT: The nature of the quantum valence transition is studied on the basis of the periodic Anderson model with Coulomb repulsion between f and conduction electrons. The density matrix renormalization group calculation for the ground state shows that the first-order valence transition emerges with the quantum critical point with diverging valence susceptibility. Instead of the phase separation in the mean-field result, quantum fluctuations generate a wide region of crossover between the Kondo and mixed valence states. It is found that the superconducting correlation is developed in the Kondo regime near the quantum critical point of the valence transition. The origin is ascribed to the enhanced coherent motion of electrons with valence fluctuation. Remarks on the valence transition are given in connection with Ce compounds and Ce metal.
  Journal of Magnetism and Magnetic Materials 310(2):841-843. · 1.78 Impact Factor