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تسجيل مستخدم جديدThe absence of superconductivity in the next-to-leading order Ginzburg-Landau functional for Bardeen-Cooper-Schrieffer superconductor
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Shortly after the Gorkovs microscopic derivation of Ginzburg-Landau model via a small order parameter expansion in BCS theory, the derivation was carried to next-to-leading order in that parameter and its spatial derivatives. The aim was to obtain a generalized Ginzburg-Landau free energy that approximates the microscopic model better. We prove that the resulting extended Ginzburg-Landau functional does not support a superconducting state since it does not have any solutions in the form of free energy minima.
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