Pseudogap Phase Formation in the Crossover from Bose-Einstein Condensation to BCS Superconductivity in Low-Dimensional Systems
| Autor: | Sergei G. Sharapov, R. M. Quick, V. P. Gusynin, Vadim M. Loktev |
|---|---|
| Rok vydání: | 1998 |
| Předmět: |
Condensed Matter::Quantum Gases
Physics Superconductivity Condensed matter physics Condensed Matter - Superconductivity Degrees of freedom (physics and chemistry) FOS: Physical sciences Statistical and Nonlinear Physics Fermion Condensed Matter Physics law.invention Superconductivity (cond-mat.supr-con) law Condensed Matter::Superconductivity Phase (matter) Pseudogap Bose–Einstein condensate Phase diagram Boson |
| Zdroj: | ResearcherID Scopus-Elsevier Web of Science |
| ISSN: | 1793-6578 0217-9792 |
| DOI: | 10.1142/s0217979298002015 |
| Popis: | A phase diagram for a 2D metal with variable carrier density has been studied using the modulus-phase representation for the order parameter in a fully microscopic treatment. This amounts to splitting the degrees of freedom into neutral fermion and charged boson degrees of freedom. Although true long range order is forbidden in two dimensions, long range order for the neutral fermions is possible since this does not violate any continuous symmetry. The phase fluctuations associated with the charged degrees of freedom destroy long range order in the full system as expected. The presence of the neutral order parameter gives rise to new features in the superconducting condensate formation in low dimensional systems. The resulting phase diagram contains a new phase which lies above the superconducting (here Berezinskii-Kosterlitz-Thouless) phase and below the normal (Fermi-liquid) phase. We identify this phase with the pseudogap phase observed in underdoped high-$T_{c}$ superconducting compounds above their critical temperature. We also find that the phase diagram persists even in the presence of weak 3-dimensionalisation. 4 pages, LaTeX; invited paper presented at New^3SC-1, Baton Rouge, USA, 1998. To be published in Int.J.Mod.Phys.B |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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