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In-plane polarized collective modes in detwinned YBa$_{2}$Cu$_{3}$O$_{6.95}$ observed by spectral ellipsometry

C. Bernhard·T. Holden·J. Humlíček·D. Munzar·A. Golnik·M. Kläser·Th. Wolf·L. Carr·C. Homes·B. Keimer·M. Cardona
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Abstract

The in-plane dielectric response of detwinned YBa$_{2}$Cu$_{3}$O$_{6.95}$ has been studied by far-infared ellipsometry. A surprisingly lare number of in-plane polarized modes are observed. Some of them correspond to pure phonon modes. Others posses a large electronic contribution which strongly increases in the superconducting state. The free carrier response and the collective modes exhibit a pronounced a-b anisotropy. We discuss our results in terms of a CDW state in the 1-d CuO chains and induced charge density fluctuations within the 2-d CuO$_{2}$ planes.

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C. Bernhard, T. Holden, J. Humlíček, D. Munzar, A. Golnik, M. Kläser, Th. Wolf, L. Carr, C. Homes, B. Keimer, M. Cardona. 2001-07-27. In-plane polarized collective modes in detwinned YBa$_{2}$Cu$_{3}$O$_{6.95}$ observed by spectral ellipsometry. https://doi.org/10.1016/s0038-1098(01)00451-3

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