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Magnetic density of states at low energy in geometrically frustrated systems

A. Yaouanc·P. Dalmas de Reotier·V. Glazkov·C. Marin·P. Bonville·J. A. Hodges·P. C. M. Gubbens·S. Sakarya·C. Baines
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Abstract

Using muon-spin-relaxation measurements we show that the pyrochlore compound Gd2Ti2O7, in its magnetically orderered phase below ~ 1 K, displays persistent spin dynamics down to temperatures as low as 20 mK. The characteristics of the induced muon relaxation can be accounted for by a scattering process involving two magnetic excitations, with a density of states characterized by an upturn at low energy and a small gap depending linearly on the temperature. We propose that such a density of states is a generic feature of geometrically frustrated magnetic materials.

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A. Yaouanc, P. Dalmas de Reotier, V. Glazkov, C. Marin, P. Bonville, J. A. Hodges, P. C. M. Gubbens, S. Sakarya, C. Baines. 2005-06-17. Magnetic density of states at low energy in geometrically frustrated systems. https://doi.org/10.1103/physrevlett.95.047203

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