Effect of the Electron-Phonon Interaction on the Self-Trapped Magnetic Polaron

Effect of the electron-phonon interaction on the large self-trapped magnetic polaron is studied for the antiferromagnetic semiconductor at T =0 K, in which both the acoustical and the optical phonon branch are taken into consideration. The electron-phonon interaction couples the magnetic polaron with the lattice deformation and thus reduces the radius of the magnetic polaron and stabilizes it. As the effective radius of the magnetic polaron becomes larger, the interaction with the optical branch is more effective than that with the acoustical branch. Furthermore, the self-trapped magnetic polaron in EuTe and its possibility are discussed on the basis of the detailed calculation. Some comments and discussions for related experimental results for EuTe are given. Effect on the small self-trapped magnetic polaron is also discussed on the basis of a simplified model.