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Andreev-reflection and Point-Contact Spectroscopy of Superconducting Rare Earth Transition Metal Borocarbides

I. K. Yanson
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Abstract

The superconducting energy gap and quasiparticle density of states (DOS) is measured by means of Andreev-reflection spectroscopy in normal metal - superconductor point contacts. It is found that both in paramagnetic and in antiferromagnetically ordered states (Tm- and Dy-compounds) the DOS has the BCS-like form while in Er- the dip in the temperature dependence of the gap is observed at the Neel temperature. In Ho-compound, the non-BCS-like form of DOS is observed in the temperature region where the incommensurate spin density waves exist along the axes a and c . Inelastic point-contact spectroscopy performed on these compounds shows that the low-frequency phonons are important for the superconducting state which are strongly mixed with the magnetic excitation branches in magnetic superconductors.

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I. K. Yanson. 2000-08-02. Andreev-reflection and Point-Contact Spectroscopy of Superconducting Rare Earth Transition Metal Borocarbides. https://arxiv.org/abs/cond-mat/0008030

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