Crystal Chemical Concept of Arrangement and Function of Layered Superconducting Materials

L. M. Volkova; S. A. Polyshchuk; S. A. Magarill; F. E. Herbeck

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Crystal Chemical Concept of Arrangement and Function of Layered Superconducting Materials

L. M. Volkova·S. A. Polyshchuk·S. A. Magarill·F. E. Herbeck

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Abstract

The crystal chemical concept of arrangement and function of layered superconducting materials is supposed. The concept is based on results of our investigation of crystal chemistry of high-temperature superconductors (HTSC) cuprates, diborides AB2 and borocarbides of nickel RNi2B2C. According to these results: (1) the main role in appearance of superconductivity played by the structural fragments - sandwiches A2(CuO2) in HTSC cuprates, A2(B2) in diborides and RB(Ni) in nickel borocarbides but not the separate planes of CuO2, B2 or Ni; (2) correlations between Tc and crystal chemical parameters of these sandwiches have similar character in all three classes of compounds, despite of distinction of a nature of their superconductivity. The central idea of the concept consists in following: in contrast to metallic conduction, for which it is enough to provide only concentration and mobility of charge carriers, for occurrence of a superconductivity it is necessary to create in addition a space (channels) for stream of charge carriers, compression of stream of carriers and focusing to direction on path of motion

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L. M. Volkova, S. A. Polyshchuk, S. A. Magarill, F. E. Herbeck. 2004-02-12. Crystal Chemical Concept of Arrangement and Function of Layered Superconducting Materials. https://arxiv.org/abs/cond-mat/0212625

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