Bounds on Superconducting Properties in Eliashberg Theory

摘要: We establish bounds on some of the properties an Eliashberg superconductor. It is shown that normalized specific heat jump at Tc and thermodynamic critical field deviation function, are bounded above by a value not much greater than observed in known superconductors. Also, lower limit exists for dimensionless ratio γ(0)T c 2 /H (0). Here γ(0) Sommerfeld constant, temperature Hc(0) zero field. On other hand, twice gap edge to can rise 11.5 reduced upper magnetic clean 1.5. Finally, results presented very strong coupling which we mean taken be comparable size typical phonon energy.