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arXiv · 0705.3520

Evidences for pairing of nearly-free quasiparticles from paraconductivity in layered superconducting cuprates

S. Caprara·M. Grilli·B. Leridon·J. Vanhacken
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Abstract

We revisit the Aslamazov-Larkin theory of paraconductivity in two dimensions, to distinguish its universal features from the specific features of nearly-free paired fermions. We show that both the numerical prefactor and the temperature dependence of the experimental paraconductivity in underdoped La_{2-x}Sr_xCuO_4 are only compatible with pairing of nearly-free fermionic quasiparticles. This conclusion is strengthened by the analysis of paraconductivity data in the presence of a finite magnetic field, from which we extract a rather low value of the critical field H_{c2}(T=0).

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S. Caprara, M. Grilli, B. Leridon, J. Vanhacken. 2008-09-25. Evidences for pairing of nearly-free quasiparticles from paraconductivity in layered superconducting cuprates. https://arxiv.org/abs/0705.3520

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