| Issue |
J. Phys. IV France
Volume 131, December 2005
|
|
|---|---|---|
| Page(s) | 49 - 54 | |
| DOI | https://doi.org/10.1051/jp4:2005131010 | |
| Published online | 18 January 2006 | |
S. Brazovskii, P. Monceau and N. Kirova
J. Phys. IV France 131 (2005) 49-54
DOI: 10.1051/jp4:2005131010
Feshbach shape resonances in nanoscale multiband systems for high Tc superconductivity
M. Filippi1, A. Bianconi1 and A. Bussmann-Holder21 Department of Physics, University of Rome La Sapienza, Ple. A. Moro 2, 00185 Roma, Italy
2 Max-Planck-Institute for Solid State Research, Heisenbergstr. 1, 70569 Stuttgart, Germany
Abstract
We show that electron doped MgB2, made of a superlattice of boron honeycomb layers,
is a multiband superconductor in the clean limit that provides the simplest high T
superconducting system (HTcS) called also the atomic hydrogen for HTcS. The chemical
potential has been tuned by atomic substitution keeping the superconductivity in the
clean limit. This is a two component electronic system made of a first Fermi gas in the
subband that coexists with a second low density electron fluid in the 
subband close the localization limit
. The Feshbach shape
resonance of the interband exchange-like pairing term centered at the 2D to 3D Lifshitz
electronic topological transition (
ETT) is shown to be the key term
controlling the critical temperature in the range from 0.3 K to 40 K.
© EDP Sciences 2005