Related papers: Pair fluctuation effects above $T_{\rm c}$
We investigate magnetic properties and effects of pairing fluctuations in the BCS (Bardeen-Cooper-Schrieffer)-BEC (Bose-Einstein condensation) crossover regime of an ultracold Fermi gas. Recently, Liu and Hu, and Parish, pointed out that…
Recently, the possibility of inducing superconductivity for electrons in two dimensional materials has been proposed via cavity-mediated pairing. The cavity-mediated electron-electron interactions are long range, which has two main effects:…
Spin fluctuations enter the calculation of the superconducting transition temperature T$_c$ only in the next-to-leading order (i.e., in O(1/N$^2$) of the 1/N expansion of the t-J model. We have calculated these terms and show that they have…
Pairing transition at finite temperature was investigated by the shell model and BCS calculations. The definitive signature of pairing transition is identified by a "transition temperature" $T_t$ estimated from a "thermal" odd-even mass…
The pairing mechanism in iron-based superconductors is the subject of ongoing debate. Proximity to an antiferromagnetic phase suggests that pairing is mediated by spin fluctuations, but orbital fluctuations have also been invoked. The…
We investigate superfluid properties and strong-coupling effects in a one-component Fermi gas with an anisotropic p-wave interaction. Within the framework of the Gaussian fluctuation theory, we determine the superfluid transition…
Pairing of fermions lies at the heart of superconductivity, the hierarchy of nuclear binding energies and superfluidity of neutron stars. The Hubbard model of attractively interacting fermions provides a paradigmatic setting for fermion…
We study the BCS--BEC crossover of the large $N$ attractive Fermi-Hubbard model on a one-dimensional lattice using the mean field approximation in the presence of an imaginary chemical potential. We show that the crossover is governed by…
Using the negative U Hubbard model we analyze normal state properties of a superconductor. In this model there exists a characteristic pairing temperature T_P above a superconducting critical temperature. Below T_P electrons start to form…
We study the superfluid critical temperature in a two-band attractive Fermi system with strong pairing fluctuations associated with both interband and intraband couplings. We focus specifically on a configuration where the intraband…
Based on the analogy between the Nambu--Jona-Lasinio model of chiral symmetry breaking and the BCS theory of superconductivity, we investigate the effect of $\bar q q$ pair fluctuations on the chiral phase transition. We include uncondensed…
This paper addresses the transition from the normal to the superfluid state in strongly correlated two dimensional fermionic superconductors and Fermi gases. We arrive at the Berezinskii-Kosterlitz-Thouless (BKT) temperature…
A link between the spin fluctuation and the "fermiology" is explored for the single-band Hubbard model within the fluctuation exchange (FLEX) approximation. We show that the experimentally observed peak position of the spin structure in the…
We study the interplay between superconductivity and non-Fermi liquid behavior of a Fermi surface coupled to a massless $SU(N)$ matrix boson near the quantum critical point. The presence of thermal infrared singularities in both the…
The possibility of thermal and quantum fluctuations induced attractive interaction leading to a pairing gap \Delta_tq in the single-particle spectrum of d-p model in the limit of a large N of fermion flavor is investigated analytically.…
We analyse the behaviour of hyperons with strangeness $S=-1$,$-2$,$-3$ in the hadronic and quark gluon plasma phases, with particular interest in parity doubling and its emergence as the temperature grows. This study uses our FASTSUM…
We study the Hubbard model on a bilayer with repulsive on-site interactions, $U$, in which fermions undergo both intra-plane ($t$) and inter-plane ($t_z$) hopping. This situation is what one would expect in high-temperature superconductors…
We study the pair-breaking effect of rotation on a cold Fermi gas in the BCS-BEC crossover region. In the framework of BCS theory, which is supposed to be qualitatively correct at zero temperature, we find that in a trap rotating around a…
A correlated fermion system is considered surrounding a finite cavity with virtual levels. The pairing properties are calculated and the influence of the cavity is demonstrated. To this end the Gell-Mann and Goldberger formula is…
If phase coherence determines the superconducting transition temperature Tc in the cuprate oxides, it is of great interest to understand the role that dynamics of the phase fluctuation plays in bringing about depletion of the…