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arXiv · 0710.4104

Bosonic spectral density of epitaxial thin-film La1.83Sr0.17CuO4 superconductors from infrared conductivity measurements

J. Hwang·E. Schachinger·J. P. Carbotte·F. Gao·D. B. Tanner·T. Timusk
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Abstract

We use optical spectroscopy to investigate the excitations responsible for the structure in the optical self-energy of thin epitaxial films of La1.83Sr0.17CuO4. Using Eliashberg formalism to invert the optical spectra we extract the electron-boson spectral function and find that at low temperature it has a two component structure closely matching the spin excitation spectrum recently measured by magnetic neutron scattering. We contrast the temperature evolution of the spectral density and the two-peak behavior in La2-xSrxCuO4 with another high temperature superconductor Bi2Sr2CaCu2O8+d. The bosonic spectral functions of the two materials account for the low Tc of LSCO as compared to Bi-2212.

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J. Hwang, E. Schachinger, J. P. Carbotte, F. Gao, D. B. Tanner, T. Timusk. 2008-04-11. Bosonic spectral density of epitaxial thin-film La1.83Sr0.17CuO4 superconductors from infrared conductivity measurements. https://doi.org/10.1103/physrevlett.100.137005

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