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arXiv · 1312.1082

Lattice dynamical signature of charge density wave formation in underdoped YBa2Cu3O6+x

M. Bakr·S. M. Souliou·S. Blanco-Canosa·I. Zegkinoglou·H. Gretarsson·J. Strempfer·T. Loew·C. T. Lin·R. Liang·D. A. Bonn·W. N. Hardy·B. Keimer·M. Le Tacon
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Abstract

We report a detailed Raman scattering study of the lattice dynamics in detwinned single crystals of the underdoped high temperature superconductor YBa2Cu3O6+x (x=0.75, 0.6, 0.55 and 0.45). Whereas at room temperature the phonon spectra of these compounds are similar to that of optimally doped YBa2Cu3O6.99, additional Raman-active modes appear upon cooling below ~170-200 K in underdoped crystals. The temperature dependence of these new features indicates that they are associated with the incommensurate charge density wave state recently discovered using synchrotron x-ray scattering techniques on the same single crystals. Raman scattering has thus the potential to explore the evolution of this state under extreme conditions.

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M. Bakr, S. M. Souliou, S. Blanco-Canosa, I. Zegkinoglou, H. Gretarsson, J. Strempfer, T. Loew, C. T. Lin, R. Liang, D. A. Bonn, W. N. Hardy, B. Keimer, M. Le Tacon. 2013-12-04. Lattice dynamical signature of charge density wave formation in underdoped YBa2Cu3O6+x. https://doi.org/10.1103/physrevb.88.214517

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