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arXiv · 1703.10270

Illumination effect by visible continuous-wave laser on bulk 40 K-superconductors

Jiro Kitagawa·Tatsuya Yoshika·Nobuhiro Gonda
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Abstract

Visible CW (continuous wave) -laser heating effects on the bulk superconductors CeFeAsO0.65F0.35 and MgB2 with 1.5 mm thickness have been investigated by measuring the temperature dependence of electrical resistivity. Each compound shows a critical-temperature Tc reduction with increasing fluence rate. At the normal state, a parallel circuit model based on the Fourier's law can well reproduce the temperature dependence of electrical resistivity of illuminated sample. On the other hand, the predicted temperature-rise due to the laser heating in the superconducting state is much smaller than the observed Tc-reduction. A temperature gradient of a few K across the sample thickness easily triggers the destruction of bulk superconductivity. Furthermore we have found a slight Tc-enhancement in CeFeAsO0.65F0.35 after a rather high fluence-rate irradiation.

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Jiro Kitagawa, Tatsuya Yoshika, Nobuhiro Gonda. 2017-03-29. Illumination effect by visible continuous-wave laser on bulk 40 K-superconductors. https://arxiv.org/abs/1703.10270

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