Thermodynamic Magnetic Field and Specific Heat Jump of a Bulk Superconductor MgB_2 Using Two-Band Ginzburg-Landau Theory

摘要

Temperature dependence of the thermodynamic magnetic field for the superconducting magnesium diboride, MgB_2, is studied in the vicinity of T_c using a two-band Ginzburg-Landau (G-L) theory. The results are shown to be in good agreement with calculations from experimental data. In addition, the two-band G-L theory gives a smaller specific heat jump, than a single-band G-L theory.