Superconducting properties of the 2D models with different types of inter-particle coupling

TL;DR

This paper reviews the superconducting properties of 2D fermion systems with various inter-particle couplings, analyzing the crossover between Bose-Einstein condensation and BCS superconductivity, considering fluctuations and interaction effects.

Contribution

It provides a comprehensive analysis of how different inter-particle couplings influence superconductivity and the BEC-BCS crossover in 2D systems, including fluctuation effects.

Findings

Crossover from BEC to BCS regimes depends on carrier density and coupling.

Interaction form significantly affects superconducting behavior.

Gaussian fluctuations impact the gap and physical properties.

Abstract

The superconducting properties of the 2D fermion system with local and different types of the indirect boson-exchange attractions in the cases of s-wave and d-wave pairing are reviewed and analysed at T=0. In particular, the possibility of the crossover from the Bose-Einstein condensation regime to the BCS-like superconductivity with the carrier density and coupling changing in the case of different pairing channels is discussed. Gaussian fluctuations of the order parameter are taken into account and the carrier density dependence of the gap is studied in this case. The role of the interaction form in the physical behavior of the systems is also discussed.