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arXiv · 1009.4290

Temperature- and Magnetic-Field-Dependent Optical Properties of Heavy Quasiparticles in YbIr2Si2

T. Iizuka·S. Kimura·A. Herzog·J. Sichelschmidt·C. Krellner·C. Geibel·F. Steglich
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Abstract

We report the temperature- and magnetic-field-dependent optical conductivity spectra of the heavy electron metal YbIr$_2$Si$_2$. Upon cooling below the Kondo temperature ($T_{\rm K}$), we observed a typical charge dynamics that is expected for a formation of a coherent heavy quasiparticle state. We obtained a good fitting of the Drude weight of the heavy quasiparticles by applying a modified Drude formula with a photon energy dependence of the quasiparticle scattering rate that shows a similar power-law behavior as the temperature dependence of the electrical resistivity. By applying a magnetic field of 6T below $T_{\rm K}$, we found a weakening of the effective dynamical mass enhancement by about 12% in agreement with the expected decrease of the $4f$-conduction electron hybridization on magnetic field.

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T. Iizuka, S. Kimura, A. Herzog, J. Sichelschmidt, C. Krellner, C. Geibel, F. Steglich. 2010-10-08. Temperature- and Magnetic-Field-Dependent Optical Properties of Heavy Quasiparticles in YbIr2Si2. https://doi.org/10.1143/jpsj.79.123703

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