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Photoexcited electron dynamics in Kondo insulators and heavy fermions

Jure Demsar·Verner K. Thorsmolle·John L. Sarrao·Antoinette J. Taylor
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Abstract

We have studied the photoexcited carrier relaxation dynamics in the Kondo insulator SmB6 and the heavy fermion metal YbAgCu4 as a function of temperature and excitation level. The dynamic response is found to be both strongly temperature dependent and nonlinear. The data are analyzed with a Rothwarf-Taylor bottleneck model, where the dynamics are governed by the presence of a narrow gap in the density of states near the Fermi level. The remarkable agreement with the model suggests that carrier relaxation in a broad class of heavy electron systems (both metals and insulators) is governed by the presence of a (weakly temperature dependent) hybridization gap.

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Jure Demsar, Verner K. Thorsmolle, John L. Sarrao, Antoinette J. Taylor. 2005-12-06. Photoexcited electron dynamics in Kondo insulators and heavy fermions. https://doi.org/10.1103/physrevlett.96.037401

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