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Hall Effect anomalies near Quantum Critical Point in CeCu6-xAux

N. E. Sluchanko·V. V. Glushkov·S. V. Demishev·N. A. Samarin·G. S. Burhanov·O. D. Chistiakov·D. N. Sluchanko
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Abstract

Precision measurements of the Hall effect have been carried out for both archetypal heavy fermion compound - CeCu6 and exemplary solid solutions CeCu6-xAux (x= 0.1 and 0.2) with quantum critical behavior. The experimental results have been obtained by technique with a sample rotation in magnetic field in the temperature range 1.8-300K. The experiment revealed a complex activation type dependence of the Hall coefficient RH(T) in CeCu6 with activation energies Ea1/kB = 110K and Ea2/kB = 1.5K in temperature ranges 50-300K and 3-10K, respectively. Microscopic parameters of charge carriers transport (effective masses, relaxation time) and localization radii ap1,2* of heavy fermions (ap1*(T>50K)= 1.7 A and ap2*(T<20K)= 14 A) were estimated for CeCu6. The second angular harmonic contribution has been established in the Hall voltage of CeCu5.9Au0.1 and CeCu6 at temperatures below T*=24K. A hyperbolic type divergence of the second harmonic term in Hall effect RH2(T)= C(1/T-1/T*) at low temperatures is found to be accompanied with a power-law behavior RH(T)= T -0.4 of the main contribution in the Hall coefficient for CeCu5.9Au0.1 compound with quantum critical behavior.

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N. E. Sluchanko, V. V. Glushkov, S. V. Demishev, N. A. Samarin, G. S. Burhanov, O. D. Chistiakov, D. N. Sluchanko. 2005-06-20. Hall Effect anomalies near Quantum Critical Point in CeCu6-xAux. https://arxiv.org/abs/cond-mat/0506502

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