Pauli paramagnetism enhancement and unusual magnetic ordering in CeB6

Abstract: Precision measurements of charge transport parameters and magnetization have been carried out on the high-quality single crystals of CeB6 at temperatures 1.8–300K. It is shown that in the temperature interval of 5K<T<T*∼80K the magnetic contribution in resistivity obeys the power law ρ m∼T −0.4, which corresponds to the regime of weak localization of charge carriers. At the same temperatures an asymptotic behavior of thermopower S∼−ln T is found together with nearly constant and negative Hall coefficient R H(T) and an essential decrease of the charge carriers mobility μ H(T)=R H(T)/ρ(T). Instead of the Curie–Weiss type dependence, an asymptotic form χ(T)∼T −0.8 is obtained for susceptibility of CeB6 in the range 15–300K. Such a behavior of transport and magnetic characteristics contradict to the predictions of Kondo-lattice approach for this archetypal SCES. An alternative interpretation is developed at present study and based on (i) the itinerant paramagnetism and DOS renormalization at temperatures below T*∼80K and (ii) realization of a complex H–T magnetic phase diagram, which is caused by a competition between SDW and 4f-antiferromagnetism in CeB6. [Copyright &y& Elsevier]