Anomalous electron transport in magnetic multilayers tuned by electric and magnetic fields

Abstract

We report on anomalous quantum electron transport in low dimensional systems, which may be tuned by varying electric and magnetic fields. In magnetic trilayers Co/M/Co (Mnonmagnetic metallic spacer), which have been used to reveal ground state of disordered two-dimensional metal, at low temperatures a crossover from the logarithmic to the anomalous non-Fermi liquid behavior (Δρ~β*√T) is observed. This crossover is probably due to scattering of electrons by symmetrical two-level systems. We also demonstrate that magnetic multilayers, with enhanced spin dependent scattering effects, may be used to study quantum magnetic phase (QPT) transition phenomena. We observed that through phase transition from antiferromagnet to the ferromagnet induced by magnetic field the spindependent contribution to the resistivity varies as Δρs ~T α with α=f(H). In the vicinity of QPT, the spin dependent contribution to the resistivity varies linearly with temperature.