ESR investigations on Ca perovskite

Authors

M. Chipara, University of Nebraska-LincolnFollow
Sy-Hwang Liou, University of Nebraska-LincolnFollow
C.N. Borca, University of Nebraska-Lincoln
R. Shoemaker, University of Nebraska-Lincoln
Shireen Adenwalla, University of Nebraska-LincolnFollow
Peter A. Dowben, University of Nebraska-LincolnFollow

Date of this Version

5-1-2000

Comments

Published in Mat. Res. Soc. Symp. Proc. Vol. 614. © 2000 Materials Research Society. Permission to use.

Abstract

Electron spin resonance studies on fine powders of La_0.65Ca_0.35MnO₃, performed in the X band, are reported. The coexistence of paramagnetic and ferromagnetic phases, in a narrow temperature range close to the Curie temperature, is observed. The electron spin resonance measurements do not support the presence of bipolarons above the Curie temperature. Temperature dependence of the ESR linewidth is governed by the hopping of polarons and the corresponding activation energy is about 150 meV above T_c.