Magnetic Field Enhancement of the Hall Effect in Dilute Magnetic System $La_{1 - x}Ce_{x}B_6$ (x ≤ 0.1)

Magnetic field dependences of the Hall coefficient $R_{H}$ and resistivity have been studied in detail for dilute magnetic compounds $La_{1-x}Ce_{x}B_6$ (x ≤ 0.1) at temperatures 1.8-300 K. It was established that the regime of weak localization of charge carriers, which was observed in these heavy fermion systems below 30 K destroys gradually in magnetic field up to 8 T. Moreover, in addition to the strong negative magnetoresistance (Δρ/ρ ≈ 80%) a drastic enhancement of the negative Hall coefficient in magnetic field (Δ $R_{H}//R_{H}$ ≈ 50%) has been deduced at liquid helium temperatures. The results of comprehensive analysis contradict the predictions of Kondo-impurity approach for this archetypal strongly correlated electron system in the dilute impurity limit. An alternative interpretation of $La_{1-x}Ce_{x}B_6$ properties is developed on the basis of spin-polaron approach, Pauli paramagnetism and the density of states renormalization effects at low temperatures.