Посилання:Advances in point-contact spectroscopy: two-band superconductor MgB₂ (Review Article) / I.K. Yanson, Yu.G. Naidyuk // Физика низких температур. — 2004. — Т. 30, № 4. — С. 355-372. — Бібліогр.: 54 назв. — англ.
Підтримка:The authors are grateful to N.L. Bobrov, P.N.
Chubov, V.V. Fisun, O.E. Kvitnitskaya, L.V. Tyutrina
for collaboration during the MgB2 investigation.
IKY thanks the Institute of Solid State Physics in For-
schungzentrum Karlsruhe for hospitality, and Prof.
H. von Löhneysen for constant support. The work in
Ukraine was supported by the State Foundation of
Fundamental Research under Grant F7/528-2001.
Analysis of the point-contact spectroscopy (PCS) data on the new dramatic high-Tc superconductor
magnesium diboride MgB₂ reveals quite different behavior of two disconnected σ and π electronic
bands, deriving from their anisotropy, different dimensionality, and electron—phonon interaction.
PCS allows direct registration of both the superconducting gaps and electron—phonon
interaction spectral function of the two-dimensional σ and three-dimensional π band, establishing
correlation between the gap value and intensity of the high-Tc driving force — the E₂g boron vibration
mode. PCS data on some nonsuperconducting transition-metal diborides are surveyed for comparison.