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Direct test of pairing fluctuations in the pseudogap phase of underdoped cuprates

N. Bergeal·J. Lesueur·M. Aprili·G. Faini·J. P. Contour·B. Leridon
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Abstract

We report on a direct test of pairing fluctuations in the pseudogap regime of underdoped superconducting cuprates using a Josephson junction. In this experiment, the coupling between a rigid superconducting pair field and pairing fluctuations produces a strong specific signature in the current-voltage characteristics. Our results show that fluctuations survive only close to Tc (T-Tc<15K) and therefore cannot be responsible for the opening of the pseudogap at high temperature.

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N. Bergeal, J. Lesueur, M. Aprili, G. Faini, J. P. Contour, B. Leridon. 2006-03-27. Direct test of pairing fluctuations in the pseudogap phase of underdoped cuprates. https://arxiv.org/abs/cond-mat/0601265

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