Superconducting critical temperature and electrical resistivity of the system Y1−xPrxBa2Cu3O6.95 (0⩽x⩽1)

doi:10.1016/0921-4534(92)90642-P

Physica C: Superconductivity

Volume 191, Issues 1–2, 1 February 1992, Pages 158-166

https://doi.org/10.1016/0921-4534(92)90642-P Get rights and content

Abstract

Measurements of the temperature dependence of the electrical resistivity of polycrystalline specimens of Y_1−xPr_xBa₂Cu₃O_6.95±0.02 (0⩽x⩽1) are reported. The electrical resistivity exhibits metallic behaviour for 0⩽x⩽0.50 and T_c, where T_c is the superconducting critical temperature, and 0.50 < x ⩽0.58 when $T⪆ 100 K$ . the resistivity determenined values of T_c decrease monotonically with x ≈ 0.57. The T_c versus x curve does not confrom to the universal relation based on the theory of Abrikosov and Gor'kov. However, for 0⪅x⪅0.3, the T_c versus x curve can be described by an empirical relation which incorporates the filling (or localization) of mobile holes in the CuO₂ planes and superconducting electron pair breaking. Methods of sample preparation are discussed.

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To date, this suppression has been believed to be better explained in terms of a model based upon the hybridization between the 4f(Pr) orbital and the neighboring 2pπ(O) orbital in the CuO2 plane [1]; where the intrinsic mobile holes become inactive because they are localized by the hybridized orbitals, giving no contribution to the superconductivity. For inspecting the roles of Pr and various dopant elements in reference to the superconducting suppression or the above hybridization, extensive experiments have been carried out for R-123 by doping with trivalent rare earth or divalent alkaline-earth elements [2–20]. In particular, much attention has been paid on the structural control by substituting cations having various sizes or valences for ingredient elements in Pr-123 in order to examine behavior of the hybridization [13–20].
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¹: Present address: Sektion Physik, Universität München, Schellingtrasse 4, D-8000 München 19, Germany.

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Superconducting critical temperature and electrical resistivity of the system Y1−xPrxBa2Cu3O6.95 (0⩽x⩽1)

Abstract

Physica B

Solid State Commun.

Physica C

Phys. Rev. B

Phys. Rev. B

J. Less-Common Met.

Z. Physik

Solid State Commun.

Phys. Rev. Lett.

Phys. Rev. B

Physica C

Nature

J. Phys. B

Phys. Rev. B

Phys. Rev. Lett.

Phys. Rev. B

Phys. Rev. B

Phys. Rev. B

J. Appl. Phys.

Phys. Rev. B

Phys. Rev. B

Phys. Rev. B

Superconducting critical temperature and electrical resistivity of the system Y_1−xPr_xBa₂Cu₃O_6.95 (0⩽x⩽1)