Resonant and crossover phenomena in a multiband superconductor: Tuning the chemical potential near a band edge

Data di pubblicazione: 19 Nov 2010

RivistaFonte dati: OPENALEXTipo OpenAlex: articleOpen Access
Autori: Davide Innocenti, Nicola Poccia, Alessandro Ricci, Antonio Valletta, S. Caprara, Andrea Perali, Antonio Bianconi

Resonances in the superconducting properties, in a regime of crossover from BCS to mixed Bose-Fermi superconductivity, are investigated in a two-band superconductor where the chemical potential is tuned near the band edge of the second miniband generated by quantum confinement effects. The shape resonances at $T=0$ in the superconducting gaps (belonging to the class of Feshbach-like resonances) is manifested by interference effects in the superconducting gap at the first large Fermi surface when the chemical potential is in the proximity of the band edge of the second miniband. The case of a superlattice of quantum wells is considered and the amplification of the superconducting gaps at the Lifshitz transition of the type neck-collapsing of Fermi surface topology is clearly shown. The results are found to be in good agreement with available experimental data on a superlattice of honeycomb boron layers intercalated by Al and Mg spacer layers.

Fonte
Physical Review B
Volume
82
Fascicolo
18
Citazioni
139
ID archivio
7b95130c84fb9fd55e4d199e51d8e5ee
Riferimenti
Volume: 82 Issue: 18 Pages: 184528