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arXiv · 1107.1165

Eu2+ spin dynamics in the filled skutterudites EuM4Sb12 (M = Fe, Ru, Os)

F. A. Garcia·C. Adriano·G. G. Cabrera·L. M. Holanda·P. G. Pagliuso·M. A. Avila·S. B. Oseroff·C. Rettori
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Abstract

We report evidence for a close relation between the thermal activation of the rattling motion of the filler guest atoms, and inhomogeneous spin dynamics of the Eu2+ spins. The spin dynamics is probed directly by means of Eu2+ electron spin resonance (ESR), performed in both X-band (9.4 GHz) and Q-band (34 GHz) frequencies in the temperature interval 4.2 < T < 300 K. A comparative study with ESR measurements on the Beta-Eu8Ga16Ge30 clathrate compound is presented. Our results point to a correlation between the rattling motion and the spin dynamics which may be relevant for the general understanding of the dynamics of cage systems.

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F. A. Garcia, C. Adriano, G. G. Cabrera, L. M. Holanda, P. G. Pagliuso, M. A. Avila, S. B. Oseroff, C. Rettori. 2011-07-06. Eu2+ spin dynamics in the filled skutterudites EuM4Sb12 (M = Fe, Ru, Os). https://doi.org/10.1103/physrevb.84.014420

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