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Evolution of the low-frequency spin dynamics in ferromagnetic manganites

J. A. Fernandez-Baca·P. Dai·H. Y. Hwang·S-W. Cheong·C. Kloc
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Abstract

Elastic and inelastic neutron scattering was used to study two ferromagnetic manganites A$_{1-x}$B$_{x}$MnO$_3$ (x $\approx$ 0.3) with $T_c$=197.9 K and 300.9 K. The spin dynamical behavior of these is similar at low temperatures, but drastically different at temperatures around $T_c$. While the formation of spin clusters of size ($\sim20$ Å) dominates the spin dynamics of the 197.9 K sample close to $T_c$, the paramagnetic to ferromagnetic transition for the 300.9 K sample is more conventional. These results, combined with seemingly inconsistent earlier reports, reveal clear systematics in the spin dynamics of the manganites.

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J. A. Fernandez-Baca, P. Dai, H. Y. Hwang, S-W. Cheong, C. Kloc. 1997-10-15. Evolution of the low-frequency spin dynamics in ferromagnetic manganites. https://doi.org/10.1103/physrevlett.80.4012

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