Anomalous specific heat and its field dependence in the magnetic polaron system:: EuB6

Employing the Monte Carlo method and the exact diagonalization method, we have investigated the magnetic and thermal properties of the magnetic polaron system near the magnetic transition temperature. We have found that the peaks of the magnetic susceptibility and the specific heat, T-C and T-P, appear at different positions and the percolation of the magnetic polarons occurs near T-P. We have also demonstrated that these behaviors are robust in the presence of the external magnetic field.