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arXiv · 1007.0538

Hybridization gap and anisotropic far-infrared optical conductivity of URu2Si2

J. Levallois·F. Lévy-Bertrand·M. K. Tran·D. Stricker·J. A. Mydosh·Y. -K. Huang·D. van der Marel
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Abstract

We performed far-infrared optical spectroscopy measurements on the heavy fermion compound URu 2 Si 2 as a function of temperature. The light's electric-field was applied along the a-axis or the c-axis of the tetragonal structure. We show that in addition to a pronounced anisotropy, the optical conductivity exhibits for both axis a partial suppression of spectral weight around 12 meV and below 30 K. We attribute these observations to a change in the bandstructure below 30 K. However, since these changes have no noticeable impact on the entropy nor on the DC transport properties, we suggest that this is a crossover phenomenon rather than a thermodynamic phase transition.

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J. Levallois, F. Lévy-Bertrand, M. K. Tran, D. Stricker, J. A. Mydosh, Y. -K. Huang, D. van der Marel. 2010-07-04. Hybridization gap and anisotropic far-infrared optical conductivity of URu2Si2. https://doi.org/10.1103/physrevb.84.184420

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