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Observation of three-magnon light scattering in CuGeO_3

G. Els·P. H. M. van Loosdrecht·P. Lemmens·H. Vonberg·G. Güntherodt·G. S. Uhrig·O. Fujita·J. Akimitsu·G. Dhalenne·A. Revcolevschi
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Abstract

Temperature and magnetic field dependent polarized Brillouin spectra of CuGeO_3 are reported. In addition to a bound singlet state at 30 cm^{-1}, a new feature has been observed at 18 cm^{-1}. This feature is interpreted in terms of a novel three-magnon light scattering process between excited triplet states.

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G. Els, P. H. M. van Loosdrecht, P. Lemmens, H. Vonberg, G. Güntherodt, G. S. Uhrig, O. Fujita, J. Akimitsu, G. Dhalenne, A. Revcolevschi. 1997-11-06. Observation of three-magnon light scattering in CuGeO_3. https://doi.org/10.1103/physrevlett.79.5138

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