The sample overall has infinite conductivity due to the superconducting regions.
Figure 8.51 shows the dependence ofBci and BC2 on the temperature and
identifies the regions of Meissner, mixed, and normal states. All engineering applications of superconductors invariably use Type II material s because BC2 is typically much
greater than Bc found in Type I material s and, furthermore, the critical temperatures of
Type II material s are higher than those of Type I . Many superconductors, including the
recent high-7 superconductors, are ofType II . Table 8.7 summarizes the characteristics
of selected Type I and Type II superconductors