Estimation of characteristic size of ferromagnetic clusters forming above T$_C$ in Nd$_{0.75}$Ba$_{0.25}$MnO$_3$ manganite

Autor:	Lazuta, A. V., Ryzhov, V. A., Runov, V. V., Troyanchuk, I. O.
Rok vydání:	2009
Předmět:	Condensed Matter - Mesoscale and Nanoscale Physics Condensed Matter - Strongly Correlated Electrons
Druh dokumentu:	Working Paper
Popis:	We present the data on depolarization of polarized neutron beam and second harmonic of magnetization ($M_2$) for Nd$_{1-x}$Ba$_x$MnO$_3$ ($x$ = 0.23, the Curie temperature $T_C \approx$ 124 K; $x$ = 0.25, $T_C \approx$ 129 K) manganites. The depolarization starts to develop below $T$* $\approx$ 147 K $> T_C$ for both samples, being larger in x = 0.25 compound. This evidences the arising of a ferromagnetic (F) cluster phase below $T$* and a growth of its relative volume fraction with increasing doping concentration that agrees with the previously published results of $M_2$ study. A characteristic size of the F clusters and their concentration are estimated combining the neutron depolarization and $M_2$ data for $x$ = 0.25 manganite. Comment: 8 pages, 2 figures
Databáze:	arXiv
Externí odkaz:	http://arxiv.org/abs/0911.4179 Zobrazit plný text záznamu View this record from Arxiv