Magnetic transition and polaron crossover in a two-site single polaron model including double exchange interaction |
| |
Authors: | J. Chatterjee M. Mitra A.N. Das |
| |
Affiliation: | (1) Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Calcutta 700064, India, IN |
| |
Abstract: | A two-site double exchange model with a single polaron is studied using a perturbation expansion based on the modified Lang-Firsov transformation. The antiferromagnetic to ferromagnetic transition and the crossover from small to large polaron are investigated for different values of the antiferromagnetic interaction (J) between the core spins and the hopping (t) of the itinerant electron. Effect of the external magnetic field on the small to large polaron crossover and on the polaronic kinetic energy are studied. When the magnetic transition and the small to large polaron crossover coincide for some suitable range of J/t, the magnetic field has very pronounced effect on the dynamics of polarons. Received 1 June 2000 |
| |
Keywords: | PACS. 71.38.+i Polarons and electron-phonon interactions - 63.20.Kr Phonon-electron and phonon-phonon interactions - 75.30.Vn Colossal magnetoresistance |
本文献已被 SpringerLink 等数据库收录! |