2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/21644To understand the superconductivity in MgB2, several two-band models of superconductivity were proposed. In this paper, by using the relativistic fermion model, we clearize the effect of the lower band in the superconductivity.2 pages. To be published in RCNP (Osaka univ.) annual report 2002SuperconductivityStrongly Correlated ElectronsHigh Energy Physics - Phenomenologytext