Bulk superconductor in a week magnetic field will act as a perfect diamagnet , with zero magnetic induction in the interior.

Nonmagnetic impurities have no marked effect on the SC transition temperature.

A sufficiently strong magnetic field will destroy SC. At critical temperature critical field is zero H_{C}(T_{C})=0

Values of H_{C} are always low for type I superconductors.

For a given H_{C} the area under magnetization curve is same for type II SC as for type I SC.

In all SC entropy decreases markedly on cooling below transition temperature.

Superconducting state is the more ordered state.

Contribution to the heat capacity in the SC state is an exponential form with an argument proportional to -1/T

In SC the important interaction is electron-electron interaction which orders the electrons in K space with respect to the fermi gas of the electrons.

The argument of the exponential factor in the electronic heat capacity of a SC is found to be -E_{g}/2kT

The transition in zero magnetic field from the superconducting state to the normal state is the second order phase transition, not involving any latent heat but discontinuity in heat capacity.

Energy gap decreases continuity to zero as the temperature is increased to transition temperature.

For photons of energy less than energy gap , the resistivity of the superconductor vanishes at absolute zero.

As the temperature is increased not only does the gap decreases , but the resistivity for photon with energy below the energy gap no longer vanishes except at zero frequency.

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