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arXiv · 0810.3501

Family tree of perovskite-related superconductors

Hans Hermann Otto
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Abstract

A simple empirical relation has been found to exist between optimum Tc and the formal mean cation charge of perovskite-related superconductors, covering both conventional superconductors and superconducting cuprates. Tc is shown to increase exponentially with decreasing . It is suggested that a Ba-based cuprate with about 2 reach a Tc around 200 K. The strong correlation may be thought of as an indication for a common mechanism of superconductivity of the whole family of compounds. In addition, the structural assignment for the 'cubic' high-Tc phase reported by Volkov (Tc = 117 K) to the orthorhombic BaCuO2.5 prototype is proposed.

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Hans Hermann Otto. 2008-10-20. Family tree of perovskite-related superconductors. https://arxiv.org/abs/0810.3501

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