The Bogoliubov-de Gennes (BdG) Hamiltonian is presented for electron-hole superconductors with reference to YBCO having an energy gap Δm ≈ 25 meV. Metals and metallic alloys are assumed to be composed of free electron gas at room temperatures. At very low temperatures in the superconducting state, the electrons occupy a sea of levels, called Fermi sea, up to the top of the level called Fermi level EF. Above EF, there may be a very small energy gap, and then the conduction band with no electrons. On small excitation, the electron from some level in Fermi sea can shift to a vacant conduction band leaving a hole in the Fermi sea with an effective positive charge. There is the reverse transition of the electron from the conduction band to the Fermi sea, and in each case, there is a finite correlation between the electron and the hole. The values of quasi-particle energy (Ek), specific heat , and entropy are calculated when the assembly is in the superconducting state.
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