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arXiv · 1702.00717

Point-contact spectroscopy of superconducting YBaCuO single crystals of tetragonal modification

I. K. Yanson·L. F. Rybal'chenko·V. V. Fisun·N. L. Bobrov·V. V. Demirskii·V. V. Mitkevich
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Abstract

The point-contact spectra of tetragonal $\rm YBa_2Cu_3O_{7-\delta}$ with $T_c=50-60~K$ are studied at various temperatures. The single-electron energy ($2\Delta_0/kT_c\simeq 17$) and its temperature dependence are determined. The characteristic energies of quasiparticle excitations interacting with conduction electrons in this high-$T_c$. superconductor are found to correlate with the characteristic phonon energies. The possibility of a pair gap, which increases with temperature, is revealed near the critical temperature.

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I. K. Yanson, L. F. Rybal'chenko, V. V. Fisun, N. L. Bobrov, V. V. Demirskii, V. V. Mitkevich. 2017-02-02. Point-contact spectroscopy of superconducting YBaCuO single crystals of tetragonal modification. https://arxiv.org/abs/1702.00717

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