Pressure evolution of f electron hybridized state in CeCoIn5 studied by optical conductivity

International Conference on Strongly Correlated Electron Systems 2014

Okamura, H.^1 ; Takigawa, A.^1 ; Bauer, E.D.^2 ; Moriwaki, T.^3 ; Ikemoto, Y.^3

Department of Physics, Graduate School of Science, Kobe University, Kobe

657-8501, Japan^1

Los Alamos National Laboratory, Los Alamos

NM

87545, United States^2

Japan Synchrotron Radiation Research Institute, Sayo

679-5198, Japan^3

关键词: Ambient pressures;    C-f hybridization;    CeCoIn5;    Density of state;    F-electrons;    High pressure;    Low temperatures;    Pressure evolution;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/592/1/012001/pdf
DOI  :  10.1088/1742-6596/592/1/012001

来源: IOP

【 摘 要 】

Optical conductivity σ(ω) of CeCoIn5has been measured under high pressure to 8 GPa and at low temperatures to 6 K, to study the pressure evolution of the conduction (c)-f electron hybridized state near the Fermi level. At ambient pressure, CeCoIn5is a heavy fermion superconductor with Tc=2.3 K, and has moderately strong c-f hybridization. σ(ω) at ambient pressure shows a marked infrared peak due to optical excitations involving the c-f hybridized state. With increasing pressure, the infrared peak becomes broader, and its center shifts to higher energy. This result indicates that the large density of states of the c-f hybridized state becomes broader with increasing pressure, and that the peak of the density of states shifts away from the Fermi level. Althouth such pressure evolution of the c-f hybridized state had been widely assumed on the basis of theoretical consideration, the present optical result demonstrates it clearly and directly.