Academic Journal

Angular and temperature dependencies of EPR linewidth and Gorter relaxation rates in concentrated paramagnets: Application to La0.9Sr0.1MnO3 and La0.875Sr0.125MnO3.

Title: Angular and temperature dependencies of EPR linewidth and Gorter relaxation rates in concentrated paramagnets: Application to La0.9Sr0.1MnO3 and La0.875Sr0.125MnO3.
Authors: Khalvashi, E. Kh.1 enver.khalvashi@bsu.edu.ge, Fokina, N. P.2, Elizbarashvili, M. O.3
Source: Magnetic Resonance in Solids. 2017, Vol. 19 Issue 1, p1-17. 17p.
Subject Terms: *ELECTRON paramagnetic resonance, *TEMPERATURE, *SINGLE crystals, *LARMOR precession, *HEAT
Abstract: The angular and temperature dependencies of the electron paramagnetic resonance (EPR) linewidth in the weak constant field and of the relaxation rates measurable by the Gorter type experiments in zero constant magnetic field (Gorter RRs) are analytically investigated in magnetically concentrated paramagnets with the dominating exchange interaction. The consideration is restricted to the experiments, where the EPR linewidth is both anisotropic and linear over the temperature. It is suggested that under such conditions the EPR broadening is caused by the spin-lattice relaxation of the anisotropic interaction via the one-phonon mechanism. The analytical results are brought to the form suitable for the extraction of the Dzyaloshinsky-Moriya and the crystal field interaction constants from the experiment. It is shown that the EPR linewidth at the constant field direction along any crystal axis is equal to the half sum of the zero-field RRs for the two other crystal axes. The obtained results are successfully used for the interpretation of the EPR experimental results in the La0.875Sr0.125MnO3 and La0.875Sr0.125MnO3 single crystals in the Jahn-Teller strongly distorted phase in the definite temperature interval. The angular dependencies of the Gorter RRs and the EPR linewidth are presented graphically at the constant field continuous rotations in the three crystallographic planes in La0.875Sr0.125MnO3. [ABSTRACT FROM AUTHOR]
: Copyright of Magnetic Resonance in Solids is the property of Magnetic Resonance in Solids, Electronic Journal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
Database: Academic Search Complete