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Kondo Scaling in the Optical Response of YbIn_(1-x)Ag_xCu_4

Jason N. Hancock·Tim McKnew·Zack Schlesinger·John L. Sarrao·Zach Fisk
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Abstract

Theoretical work on Kondo systems predicts universality in the scaling of observable quantities with the Kondo temperature, T_K. Here we report infrared-frequency optical response measurements of the correlated system \ybinag. We observe that x-dependent variations in the frequency and strength of a low energy excitation are related to the x-dependent Kondo temperature. Comparison of the inferred trends with existing theory and a model calculation provides a framework in which to view these experimental results as scaling phenomena arising from local-moment/conduction electron hybridization.

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Jason N. Hancock, Tim McKnew, Zack Schlesinger, John L. Sarrao, Zach Fisk. 2004-03-19. Kondo Scaling in the Optical Response of YbIn_(1-x)Ag_xCu_4. https://doi.org/10.1103/physrevlett.92.186405

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