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arXiv · 1002.1029

Vortex excitations above T_c as revealed by ESR

Yu. Talanov·L. Salakhutdinov·E. Giannini·R. Khasanov
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Abstract

Using electron spin resonance (ESR) technique we have obtained data evidencing the existence of magnetic vortices in high-temperature superconductors at temperatures above the critical one $T_c$. We have studied magnetic excitations in \bis single crystals above $T_c$ with the method of surface spin decoration. The surface layer of diphenyl-picrylhydrazyl was used as a sensitive probe of magnetic field distortions. The temperature dependence of the ESR signal parameters has indicated that far above $T_c$ the magnetic flux of a sample is affected by the superconducting order parameter fluctuations while close to $T_c$ its changes are due to vortex-type excitations.

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Yu. Talanov, L. Salakhutdinov, E. Giannini, R. Khasanov. 2010-02-04. Vortex excitations above T_c as revealed by ESR. https://arxiv.org/abs/1002.1029

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