The magnetic properties of superconducting alloys. II

The lower critical field ${\mathrm{H}}_{\mathrm{c}1}$ is derived from the microscopic theory for superconducting alloys. It is shown that Abrikosov’s structure in the field just above ${\mathrm{H}}_{\mathrm{c}1}$ is described by the use of a parameter of which the temperature dependence is obtained. A brief discussion of the gap in the excitation spectrum and the thermodynamical behavior at lower temperatures is given.