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Harmonics of the AC susceptibility for the study of I-V curves in melt grown YBCO

Maria Giuseppina Adesso·Massimiliano Polichetti·Sandro Pace
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Abstract

The measurements of the 1st and the 3rd harmonics of the AC magnetic susceptibility, performed on melt grown YBCO samples as a function of the temperature and the external parameters (frequency and amplitude of AC magnetic field, intensity of a DC field) were studied by using the Cole-Cole plot analysis. By considering the AC field dependence of the 3rd harmonics Cole-Cole plots, we have extracted information about the peculiar behaviour of the I-V characteristics and, therefore, about the dissipative phenomena in the sample. The experimental results have been analysed with the help of both analytical and numerical curves. In particular, the use of a phenomenological expression for the resistivity allowed us to reproduce the main experimental features, including the observed invariance of the area inside the Cole-Cole plots and their behaviour as a function of the AC field.

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Maria Giuseppina Adesso, Massimiliano Polichetti, Sandro Pace. 2003-09-13. Harmonics of the AC susceptibility for the study of I-V curves in melt grown YBCO. https://doi.org/10.1016/j.physc.2003.09.036

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