Role of magnetic polarons in transport properties of EuB6

Abstract

In order to understand the anomalous magnetic and transport properties of a low carrier density magnetic system EuB6, the magnetic polaron model has been explored with the strong interaction between charge carriers and local magnetic moments. The role of lattice degrees of freedom and the localization effect due to impurity are also studied through the mean-field approximation and the Monte Carlo method incorporating the exact diagonalization. It has been shown that the metal-insulator transition near magnetic transition in EuB6 is naturally understandable in the framework of the magnetic polaron model. (c) 2005 American Institute of Physics.