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Point-contact investigations of challenging superconductors: two-band MgB2, antiferromagnetic HoNi2B2C, heavy fermion UPd2Al3, paramagnetic MgCNi3

Yu. G. Naidyuk·O. E. Kvitnitskaya·I. K. Yanson·G. Fuchs·K. Nenkov·S. -L. Drechsler·G. Behr·D. Souptel·K. Gloos
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Abstract

An overview on recent efforts in point-contact (PC) spectroscopy of title superconductors is given. Distinct phonon features and crystalline-electric-field effects are observed in PC spectra of HoNi2B2C. Results of study of superconducting (SC) gap and excess current versus temperature and magnetic field reflecting specific multi-band electronic structure in MgB2 are presented. The nature of the extremely nonlinear I(V) curves in the antiferromagnetic (AF) and SC state are elucidated for UPd2Al3 break-junctions and MgCNi3 point contacts.

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Yu. G. Naidyuk, O. E. Kvitnitskaya, I. K. Yanson, G. Fuchs, K. Nenkov, S. -L. Drechsler, G. Behr, D. Souptel, K. Gloos. 2004-10-19. Point-contact investigations of challenging superconductors: two-band MgB2, antiferromagnetic HoNi2B2C, heavy fermion UPd2Al3, paramagnetic MgCNi3. https://doi.org/10.1016/j.physb.2005.01.102

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