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Coherent amplitudon generation in K_0.3MoO_3 through ultrafast inter-band quasi particle decay

D. M. Sagar·A. A. Tsvetkov·D. Fausti·S. van Smaalen·P. H. M. van Loosdrecht
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Abstract

The charge density wave system K_0.3MoO_3 has been studied using variable energy pump-probe spectroscopy, ellipsometry, and inelastic light scattering. The observed transient reflectivity response exhibits quite a complex behavior, containing contributions due to quasi particle excitations, coherent amplitudons and phonons, and heating effects. The generation of coherent amplitudons is discussed in terms of relaxation of photo-excited quasi particles, and is found to be resonant with the interband plasmon frequency. Two additional coherent excitations observed in the transients are assigned to zone-folding modes of the charge density wave state.

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D. M. Sagar, A. A. Tsvetkov, D. Fausti, S. van Smaalen, P. H. M. van Loosdrecht. 2006-10-10. Coherent amplitudon generation in K_0.3MoO_3 through ultrafast inter-band quasi particle decay. https://doi.org/10.1088/0953-8984%2F19%2F34%2F346208

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