Magnetoresistance and hall effect in electron-doped superconductor Nd2 − xCexCuO4+δ with different degrees of nonstoichiometric disorder: A two-band model

Investigations have been performed on the magnetic-field dependences of the longitudinal and Hall resistivity of the electron-doped Nd2 − xCexCuO4+δ system with an optimum content of cerium (x = 0.15) and different degree of the nonstoichiometric disorder in magnetic fields of up to 8 T (B ‖ c; J ‖ ab) in a temperature range of 0.4–4.2 K. The observed anomalous dependences of the Hall coefficient R(B) along with the dependences of the electrical resistivity ρ(B) have been interpreted based on the Drude-Lorentz model in the case of the normal state and in the Bardeen-Stephen model in the mixed state modified with allowance for the coexistence of two types of charge carriers with the opposite charge signs (electrons and holes).