Superconductivity in the Model of Elastic Jelly

Abstract

In this work, a question is tackled concerning the formation of a superconducting condensate in an earlier proposed model of "elastic jelly", in which phonons of the valent skeleton play the part of initiating ones. It was shown that in distinction from the BCS theory, the momenta of forming electron couples are different from zero. This fact changes the pattern of the description of the superconductivity phenomenon in the proposed model. First, the gap in the one-electron spectrum appears due to the effect of a "mean field" on the energy of one-electron state from the side of occupied states, the nearest neighbors over the momenta grid. Second, the condensate is formed by one-electron states with energies below that of the gap edge. This is why the Fermi-condensation arises in the system. Third, in the proposed theory the electron couples appear in the form of low-energy excitations, i.e., as those with the minimum amount of energy per excitation electron. Hence, their role is minimized to that of low-energy excitation with the minimum energy per electron, and they are no more "bricks" the superconducting condensate is made of, as the case is in the BCS theory.