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arXiv · 2101.09447

Possible observation of the signature of the bad metal phase and its crossover to a Fermi liquid in K(BEDT-TTF)2Cu(NCS)2 bulk and nanoparticles by Raman scattering

M. Revelli Beaumont·P. Hemme·Y. Gallais·A. Sacuto·K. Jacob·L. Valade·D. de Caro·C. Faulmann·M. Cazayous
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Abstract

K(BEDT-TTF)2Cu(NCS)2 has been investigated by Raman scattering in both bulk and nanoparticle compounds. Phonon modes from 20 to 1600 cm-1 have been assigned. Focusing on the unexplored low frequency phonons, a plateau in frequencies is observed in the bulk phonons between 50 and 100 K and assigned to the signature of the bad metal phase. Nanoparticles of K(BEDT-TTF)2Cu(NCS)2 exhibit anomalies at 50 K associated to the crossover from a bad metal to a Fermi liquid whose origins are discussed.

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M. Revelli Beaumont, P. Hemme, Y. Gallais, A. Sacuto, K. Jacob, L. Valade, D. de Caro, C. Faulmann, M. Cazayous. 2021-01-23. Possible observation of the signature of the bad metal phase and its crossover to a Fermi liquid in K(BEDT-TTF)2Cu(NCS)2 bulk and nanoparticles by Raman scattering. https://doi.org/10.1088/1361-648x/abd813

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