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Point-Contact Spectroscopy of Superconductors

I. K. Yanson
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Abstract

The point-contact spectroscopy, in contrast to the tunneling spectrocopy, considers small electrical contacts with direct conductivity. In the normal state, it enables one to measure the spectral function of electron-boson interaction. In the superconducting state, new features appear connected with the energy dependence of excess current. The non-linearities of the current-voltage characteristic are due to: i) The inelastic scattering of electron quasiparticles in the contact region; ii) The energy dependence of the superconducting energy gap, and iii) The non-equilibrium superconducting effects. These effects are discussed from the experimental point of view

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I. K. Yanson. 2000-08-08. Point-Contact Spectroscopy of Superconductors. https://arxiv.org/abs/cond-mat/0008116

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