INFLUENCE OF LATTICE-DEFECTS ON SUPERCOND UCTING TRANSITION-TEMPERATURE OF TRANSITION-METALS

Some theoretical models are discussed which describe changes in the su perconducting transition temperature T(c) and the electron-phonon coup ling constant for metals having various types of lattice defects. The experimental results on the influence of defective structures produced by deformation at T congruent-to 300 K and T << THETA (THETA is the D ebye temperature) upon T(c) of bcc (Nb, V, Ta) and hcp (Re, Zr) transi tion metals are analysed. Theoretical calculations are compared with e xperimental results on T(c) variations in Nb with a high dislocation d ensity. The microscopic characteristics determining basic superconduct ing parameters of a transition metal with deformation-induced defects were numerically calculated.