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Pseudogap in the Optical Spectra of UPd_2Al_3

M. Dressel·B. Gorshunov·N. Kasper·B. Nebendahl·M. Huth·H. Adrian
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Abstract

The in-plane optical conductivity of UPd_2Al_3 was measured at temperatures $2 {\rm K}<T<300$ K in the spectral range from 1 cm^{-1} to 40 cm^{-1} (0.14 meV to 5 meV). As the temperature decreases below 25 K a well pronounced pseudogap of 0.2 meV develops in the optical response. In addition we observe a narrow conductivity peak at zero frequency which at 2 K is less than 1 cm^{-1} wide but which contains only a fraction of the delocalized carriers. The gap in the electronic excitations might be an inherent feature of the heavy fermioin ground state.

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M. Dressel, B. Gorshunov, N. Kasper, B. Nebendahl, M. Huth, H. Adrian. 2000-05-02. Pseudogap in the Optical Spectra of UPd_2Al_3. https://doi.org/10.1088/0953-8984%2F12%2F40%2F101

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