Speaker
Prof.
Giancarlo Calvanese Strinati
(University of Camerino)
Description
The pair correlation function and the order parameter correlation function probe,
respectively, the intra-pair and inter-pair correlations of a Fermi gas with
attractive inter-particle interaction. Here, these correlation functions are
calculated in terms of a diagrammatic approach, as a function of coupling throughout
the BCS-BEC crossover and of temperature, both in the superfluid and normal phase
across the critical temperature $T_{c}$. Several physical quantities are obtained
from this calculation, including the pair coherence and healing lengths, the Tan's
contact, the crossover temperature $T^{*}$ below which inter-pair correlations begin
to build up in the normal phase, and the signature for the disappearance of the
underlying Fermi surface which tends to survive in spite of pairing correlations. A
connection is also established with experimental data on the temperature dependence
of the normal coherence length as extracted from the proximity effect measured in
high-temperature (cuprate) superconductors.
Primary author
Prof.
Giancarlo Calvanese Strinati
(University of Camerino)
