- #1
kye
- 168
- 2
is the BCS theory of low temperature superconductivity completely accepted already? any doubters here? I encountered this paper that suggests the BCS is incomplete:
http://physics.ucsd.edu/~jorge/abstracts/bcs.pdf
"The most quoted reason given as convincing proof that BCS-electron-phonon theory describes conventional superconductors is the structure in tunneling characteristics detected in normal-insulator-superconductor tunneling experiments, where small wiggles in the tunneling
conductance as function of voltage match the peaks and valleys of the phonon density of states as function of frequency measured in neutron scattering experiments in several materials, most notably Pb[23–25].
I am not disputing the interpretation that the structure in the tunneling conductance reflects the phonon spectrum. As Bernd Matthias said[22], “you can’t ever stop a crystal lattice from rattling”. Even the gap of ordinary semiconductors is modulated (but not caused!) by the electron-phonon interaction and shows an isotope effect[26]. What I am disputing is the interpretation that the small modulation (few %) of the tunneling conductance spectrum by the phonons is proof that superconductivity is caused by lattice vibrations and would not
exist for infinite ionic mass."
Comments of the paper? What stuff is wrong there and which do you and do not agree?
http://physics.ucsd.edu/~jorge/abstracts/bcs.pdf
"The most quoted reason given as convincing proof that BCS-electron-phonon theory describes conventional superconductors is the structure in tunneling characteristics detected in normal-insulator-superconductor tunneling experiments, where small wiggles in the tunneling
conductance as function of voltage match the peaks and valleys of the phonon density of states as function of frequency measured in neutron scattering experiments in several materials, most notably Pb[23–25].
I am not disputing the interpretation that the structure in the tunneling conductance reflects the phonon spectrum. As Bernd Matthias said[22], “you can’t ever stop a crystal lattice from rattling”. Even the gap of ordinary semiconductors is modulated (but not caused!) by the electron-phonon interaction and shows an isotope effect[26]. What I am disputing is the interpretation that the small modulation (few %) of the tunneling conductance spectrum by the phonons is proof that superconductivity is caused by lattice vibrations and would not
exist for infinite ionic mass."
Comments of the paper? What stuff is wrong there and which do you and do not agree?