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Causa, M. T., S. M. Dutrús, C. Fainstein, G. Nieva, H. R. Salva, R. D. Sánchez, L. B. Steren, M. Tovar, and Zysler R. "MAGNETIC AND STRUCTURAL PROPERTIES OF SOME ABa2Cu3O7?? SUPERCONDUCTORS." International Journal of Modern Physics B 1, no. 3-4 (1987): 989–992.
Abstract: We report here normal and superconducting properties of ABa2Cu3O7?? (with A=Y, Gd, Dy, and Er) and of Fe doped YBa2Cu3O7??. Results from X-ray powder diffraction, electrical resistivity, magnetic susceptibility, ESR, and specific heat measurements are presented, leading to a characterization of the magnetic properties of these materials. The effect of structural modifications of the lattice on the superconducting properties and the relative insensitivity of Tc to the presence of magnetic moments is discussed.
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KELLY D.M., FULLERTON E.E., PARKER F.T., GUIMPEL J., BRUYNSERAEDE Y., and SCHULLER I.K. "CONNECTION BETWEEN GIANT MAGNETORESISTANCE AND ROUGHNESS IN SPUTTERED Fe/Cr SUPERLATTICES." International Journal of Modern Physics B 7, no. 1-3 (1993): 419–424.
Abstract: Detailed structural, magnetotransport, magnetization and Mössbauer measurements of sputtered Fe/Cr superlattices are presented. The interfacial roughness of the superlattice can be controlled systematically and reproducibly by sputtering at different Ar pressures. Conversion electron Mössbauer spectroscopy results indicate that the amount of interdiffusion remains constant in the films as the interfacial roughness increases. The results show that roughness enhances the magnetoresistance for all Cr thickness in the range of 10 to 40Å.
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Núñez Regueiro, M., and D. Castello. "Thermal conductivity of high temperature superconductors." International Journal of Modern Physics B 5, no. 12 (1991): 2003–2035.
Abstract: We review and analyze the data on the thermal conductivity of both ceramic and single crystal samples of high temperature superconductors. A universal pattern can be extracted and interpreted in the following way: phonons are the main heat carriers in these materials, and in the high temperature range the thermal conductivity κ is almost constant due to phonon scattering against disorder; below the superconducting transition temperature κ increases as phonon scattering against carriers condensing into the superconducting state decreases and at still lower temperatures there is a region in which a T2 law is obeyed that most probably is due to resonant phonon scattering against low energy excitations, i.e. tunneling systems similar to those found in disordered materials. The origin of the relevant disorder is discussed.
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