On the problem of the Kondo-lattice model application to CeB6

TL;DR

This study investigates charge transport in CeB6 across 1.8-300 K, revealing weak localization, Kondo effects, and excitonic ferromagnetism, with detailed measurements of resistivity, Hall, and Seebeck coefficients.

Contribution

It provides experimental evidence of Kondo-lattice behavior and weak localization in CeB6, comparing results with theoretical models and expanding understanding of its magnetic and transport properties.

Findings

Resistivity follows a power law indicating weak localization.

Thermopower exhibits a -lnT dependence.

Negative Hall coefficient anomaly at low temperatures.

Abstract

Precision measurements of charge transport parameters (resistivity, Hall and Seebeck coefficients) have been carried out on high-quality single-crystals of cerium hexaboride in a wide temperature range 1.8-300 K. It is shown that in the temperature interval of 5 K < T < T* = 80 K the magnetic contribution in resistivity obeys the power law rm = T -1/n, which corresponds to the regime of weak localization of charge carriers with the critical index 1/n = 0.39 +- 0.02. In the same temperature interval an asymptotic behavior of thermopower S = -lnT is found together with an essential decrease of the charge carriers mobility in CeB6. A negative Hall coefficient anomaly has been detected at liquid helium temperatures. The data obtained are compared with the results predicted by the Kondo-lattice model and discussed also in terms of the theory of excitonic ferromagnetism.