Quantum correction to low-temperature resistivity induced by disorder in La2/3Sr1/3MnO3–ZrO2 matrix composites

Abstract

Low-temperature transport properties were systemically studied for a series of (1 − x) La_2/3Sr_1/3MnO₃ + xZrO₂ (x = 0, 3%, 6%, and 9%) matrix composites under a weak applied magnetic field from 0 to 1 T. The nanoscaled non-magnetic ZrO₂ particles, which are introduced as a secondary phase, have been placed into ferromagnetic metal bulk ceramics La_2/3Sr_1/3MnO₃. As the density of ZrO₂ nanoparticles increases, the ferromagnetic ordering of the system, as well as the electric transport at low temperatures enhances. The dependence of the resistivity upturns of our samples on temperature and weak magnetic field are in good agreement with a combination of electron–electron interaction and weak localization.