Magnetoresistance of a highly correlated electron liquid

Abstract

The behavior in a magnetic field of a highly correlated electron liquid approaching the fermion condensation quantum phase transition from the disordered phase is considered. We show that, at sufficiently high temperatures T≥T*(x), the effective mass starts to depend on T, M* ∝T ^−1/2. This T ^−1/2 dependence of the effective mass at elevated temperatures leads to the non-Fermi liquid behavior of the resistivity, σ(T) ∝ T and at higher temperatures σ(T) ∝ T ^3/2. The application of a magnetic field B restores the common T ² behavior of the resistivity. The effective mass depends on the magnetic field, M*(B) ∝ B ^−2/3, being approximately independent of the temperature at T≤T*(B) ∝ B ^4/3. At T≥T*(B), the T ^−1/2 dependence of the effective mass is reestablished. We demonstrate that this B-T phase diagram has a strong impact on the magnetoresistance (MR) of the highly correlated electron liquid. The MR as a function of the temperature exhibits a transition from negative values of MR at T→0 to positive values at T ∝ B ^4/3. Thus, at T≥T*(B), MR as a function of the temperature possesses a node at T ∝ B ^4/3.