# Computational Challenges in Nuclear and Many-­Body Physics

September 15, 2014 to October 10, 2014
Nordita, Stockholm
Europe/Stockholm timezone

## Morning Session: BSC-BEC

Sep 22, 2014, 9:45 AM
2h
132:028 (Nordita, Stockholm)

### Speaker

Giancarlo Calvanese-Strinati

### Description

Temperature dependence of the pair coherence and healing lengths for a fermionic superfluid throughout the BCS-BEC crossover 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.

 Slides