Further test of new pairing scheme used in overhaul of BCS theory

BCS theory has to be overhauled: Reassurance from numerical survival rate

“…Previously we selectively sampled the comprehensive neutron scattering data for lead by Stedman, Almqvist and Nilsson [25] along the high symmetry directions of the metal. We achieved a good fit between theory and these selected data [19]. We observed a 0.3 meV shift of the longitudinal peak of the theoretical phonon density of states against the experimental peak, together with a similar mismatch between the theoretical and experimental peaks of α 2 F (ν) [19].…”

“…We achieved a good fit between theory and these selected data [19]. We observed a 0.3 meV shift of the longitudinal peak of the theoretical phonon density of states against the experimental peak, together with a similar mismatch between the theoretical and experimental peaks of α 2 F (ν) [19]. We suspect that the sampled neutron data may not be sufficiently representative.…”

“…Superconductivity then arises solely from residual umklapp scattering of pairs (in real crystalline systems normal and umklapp scattering always coexist and the exclusively normal scattering scenario does not arise). In a series of publications we proved the validity of this empirical rule: it allows consistent potentials for the electron-phonon interaction to be used to evaluate both normal state electrical resistivity and superconducting tunnelling conductance with high accuracy in lead, aluminium, niobium and tantalum [3,4] as well as in tungsten, iridium, molybdenum and vanadium [19,20].…”

“…We pay some attention to lead phonons. In addition to the brief review of the topic in [19] we wish to mention an interesting episode showing how far involved investigators are willing to go in order to get to the bottom of the problem. In 1989 Chen and Overhauser named lead as one of the most complicated members of the simple-metal group, posing a challenge for more than 25 years up till then [22].…”

“…Now the numerical value of T c is reduced when reasonable values of ρ(T ) are implemented. It turns out that the introduction of the empirical S(q) settles the BCS numerical issue in the cases of lead, aluminium, niobium and tantalum with high accuracy [3,4] as it does too in tungsten, iridium, molybdenum and vanadium [19,20].…”