Crossover from BCS to composite-boson (local-pair) superconductivity in quasi-2D systems

✍ Scribed by E.V. Gorbar; V.M. Loktev; S.G. Sharapov

• Publisher: Elsevier Science
• Year: 1996
• Tongue: English
• Weight: 390 KB
• Volume: 257
• Category: Article
• ISSN: 0921-4534
• DOI: 10.1016/0921-4534(95)00773-3

✦ Synopsis

The crossover from cooperative Cooper pairing to independent bound-state (composite-bosons) formation and condensation in quasi-2D systems is studied. It is shown that at low carder density the critical superconducting temperature is equal to the temperature of Bose condensation of ideal quasi-2D Bose-gas with heavy dynamical mass, meanwhile at high densities the BCS result remains valid. The evident nonmonotonical behaviour of the critical temperature as a function of the coupling constant (the energy of the two-particle bound state) is a qualitative difference of quasi-2D crossover from the 3D one.