The pseudogap and superconductivity order parameter fluctuations

The influence of superconductivity unequilibrium order parameter correlated fluctuations on the normal phase elementary excitations have been investigated. Correspondingly a fluctuating source of pairs appears in the effective Hamiltonian described using the Gaussian free energy functional. A pseudogap (E-g) is found on the Fermi surface decreasing with rising temperature. It is scaled with the parameter alpha = epsilon(F)/k(B)T(c). For smaller alpha - s E-g develops more over T-c. In non-high-T-c systems and overdoped high-T-c compounds the pseudogap is suppressed.