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تسجيل مستخدم جديدMacroscopic character of composite high temperature superconducting wires
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The d-wave symmetry of the superconducting order in the cuprate high temperature superconductors is a well established fact, and one which identifies them as unconventional. However, in macroscopic contexts -- including many potential applications ({it i.e.} superconducting wires) -- the material is a composite of randomly oriented superconducting grains in a metallic matrix, in which Josephson coupling between grains mediates the onset of long-range phase coherence. Here, we analyze the physics at length scales large compared to the size of such grains, and in particular the macroscopic character of the long-range order that emerges. While XY-glass order and macroscopic d-wave superconductivity may be possible, we show that under many circumstances -- especially when the d-wave superconducting grains are embedded in a metallic matrix -- the most likely order has global s-wave symmetry.
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