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Experimental Test of the Inter-Layer Pairing Models for High-Tc Superconductivity Using Grazing Incidence Infrared Reflectometry

J. Schutzmann·H. S. Somal·A. A. Tsvetkov·D. van der Marel·G. E. J. Koops·N. Koleshnikov·Z. F. Ren·J. H. Wang·E. Bruck·A. A. Menovsky
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Abstract

From measurements of the far-infrared reflectivity at grazing angles of incidence with p-polarized light we determined the c-axis Josephson plasma frequencies of the single layer high T_c cuprates Tl_2Ba_2CuO_6 and La_{2-x}Sr_xCuO_4. We detected a strong plasma resonance at 50 cm^{-1} for La_{2-x}Sr_xCuO_4 in excellent agreement with previously published results. For Tl_2Ba_2CuO_6 we were able to determine an upper limit of the unscreened c-axis Josephson plasma frequency 100 cm^{-1} or a c-axis penetration depth > 15 μm. The small value of $ω_J$ stands in contrast to recent a prediction based on the inter-layer tunneling mechanism of superconductivity.

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J. Schutzmann, H. S. Somal, A. A. Tsvetkov, D. van der Marel, G. E. J. Koops, N. Koleshnikov, Z. F. Ren, J. H. Wang, E. Bruck, A. A. Menovsky. 1997-02-03. Experimental Test of the Inter-Layer Pairing Models for High-Tc Superconductivity Using Grazing Incidence Infrared Reflectometry. https://doi.org/10.1103/physrevb.55.11118

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