Specific heat studies of superconductivity

Specific heat is the rate of change of the energy of a system with temperature. The principles of adiabatic and relaxation calorimetry are discussed briefly. In a superconductor the vibrations of the lattice and the free electrons contribute to the specific heat. The electronic contribution has a different temperature dependence in the normal and the superconducting states. At the superconducting transition there is a jump in the specific heat. After a short description of the different contributions, the principles of adiabatic and relaxation calorimetry are discussed briefly. Some examples are presented from studies on low temperature superconductors to illustrate the information that can be obtained from an analysis of the specific heat data. Some important features of the specific heat of high temperature superconductors are touched upon. (author)