Skip to Main content Skip to Navigation
Theses

Sur les fluctuations de phase et d'amplitude dans les supraconducteurs avec appariement précurseur

Abstract : In this thesis we study the high temperature superconductivity phenomenon on the basis of a mixture of interacting bosons and fermions. The bosons are localized electrons pairs with strong on site repulsion (hard core) and the fermions are constituted by itinerant electrons. Using a diagrammatic approach taking into account the hard core nature of the bosons, we can examine the behavior of the system as a function of doping. We focus on the phase diagram showing its connection with the experimental phase diagram of the high temperature superconductors. The pseudogap opening temperature T*, determined from the appearance of a dip in the électronique density of states, has an opposite variation as a function of doping (given by the total concentration of fermions plus bosons) as compared with the superconducting critical temperature T?. We determine that latter from the energy scale of the phase stiffness connected with the ratio of the charge carriers density and their mass. In this scenario, the increasing of T? with doping is related to the variation of the mass rather then to the variation of the superfluid charge carriers density. We analyze in this context the change-over from the phase- to amplitude-fluctuation driven superconductivity going from low to high doping.
Complete list of metadatas

https://tel.archives-ouvertes.fr/tel-00004246
Contributor : Nathalie Le Moulec <>
Submitted on : Wednesday, January 21, 2004 - 2:52:57 PM
Last modification on : Friday, December 18, 2020 - 1:34:04 PM
Long-term archiving on: : Wednesday, September 12, 2012 - 12:45:25 PM

Identifiers

  • HAL Id : tel-00004246, version 1

Collections

UJF | CNRS | UGA

Citation

Lorenzo Tripodi. Sur les fluctuations de phase et d'amplitude dans les supraconducteurs avec appariement précurseur. Matière Condensée [cond-mat]. Université Joseph-Fourier - Grenoble I, 2002. Français. ⟨tel-00004246⟩

Share

Metrics

Record views

220

Files downloads

95