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arXiv · 1209.2942

Anisotropic optical conductivity of the putative Kondo insulator CeRu$_4$Sn$_6$

V. Guritanu·P. Wissgott·T. Weig·H. Winkler·J. Sichelschmidt·M. Scheffler·A. Prokofiev·S. Kimura·T. Iizuka·A. M. Strydom·M. Dressel·F. Steglich·K. Held·S. Paschen
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Abstract

Kondo insulators and in particular their non-cubic representatives have remained poorly understood. Here we report on the development of an anisotropic energy pseudogap in the tetragonal compound CeRu$_4$Sn$_6$ employing optical reflectivity measurements in broad frequency and temperature ranges, and local density approximation plus dynamical mean field theory calculations. The calculations provide evidence for a Kondo insulator-like response within the $a-a$ plane and a more metallic response along the c axis and qualitatively reproduce the experimental observations, helping to identify their origin.

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V. Guritanu, P. Wissgott, T. Weig, H. Winkler, J. Sichelschmidt, M. Scheffler, A. Prokofiev, S. Kimura, T. Iizuka, A. M. Strydom, M. Dressel, F. Steglich, K. Held, S. Paschen. 2012-09-13. Anisotropic optical conductivity of the putative Kondo insulator CeRu$_4$Sn$_6$. https://doi.org/10.1103/physrevb.87.115129

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