Advances in point-contact spectroscopy: two-band superconductor MgB2 (A review)
arXiv:cond-mat/0402095 · doi:10.1063/1.1704612
Abstract
Analysis of the point-contact spectroscopy (PCS) data on the new dramatic high-T$_c$ superconductor MgB$_2$ reveals quite different behavior of two disconnected $Ï$ and $Ï$ 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 $Ï$ and three-dimensional $Ï$ band, establishing correlation between the gap value and intensity of the high-T$_c$ driving force -- the $E_{2g}$ boron vibration mode. PCS data on some nonsuperconducting transition-metal diborides are surveyed for comparison.
17 pages, 30 figs., will be published in Low Temp. Phys. V.30 (2004) N4