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Observation of an optical non-Fermi-liquid behavior in the heavy fermion state of YbRh$_{2}$Si$_{2}$

S. Kimura·J. Sichelschmidt·J. Ferstl·C. Krellner·C. Geibel·F. Steglich
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Abstract

We report far-infrared optical properties of YbRh$_{2}$Si$_{2}$ for photon energies down to 2 meV and temperatures 0.4 -- 300 K. In the coherent heavy quasiparticle state, a linear dependence of the low-energy scattering rate on both temperature and photon energy was found. We relate this distinct dynamical behavior different from that of Fermi liquid materials to the non-Fermi liquid nature of YbRh$_{2}$Si$_{2}$ which is due to its close vicinity to an antiferromagnetic quantum critical point.

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S. Kimura, J. Sichelschmidt, J. Ferstl, C. Krellner, C. Geibel, F. Steglich. 2006-08-29. Observation of an optical non-Fermi-liquid behavior in the heavy fermion state of YbRh$_{2}$Si$_{2}$. https://doi.org/10.1103/physrevb.74.132408

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