CARRIER–LATTICE RELAXATION FOR BROADENING EPR LINEWIDTH IN Nd0.55Sr0.45MnO3.

In this paper, we report the electron paramagnetic resonance (EPR) study of perovskite manganite Nd0.55Sr0.45MnO3. Experimental data reveal that the EPR linewidth broadens with a quasilinear manner up to 480 K. The broadening of the EPR linewidth can be understood in terms of the shortening of carrier–lattice relaxation time due to the occurrence of strong carrier–phonon interactions. Two same activation energies obtained respectively from the temperature dependence of EPR intensity and resistivity indicate that the linewidth variation is correlated to the small polaron hopping. Therefore, the carrier–lattice coupling play a major role for deciding its magnetism in the present system. [ABSTRACT FROM AUTHOR]