1998/05/06 by Ioan Kosztin, Qijin Chen, Boldizsar Janko +2 · 6 citations
Physics and Astronomy · #Physics of Superconductivity and Magnetism #Quantum and electron transport phenomena #Superconductivity in MgB2 and Alloys #cond-mat.str-el #cond-mat.supr-con
paper · pdf · doi:10.1103/physrevb.58.r5936
published as Phys. Rev. B 58, R5936 (1998). · REVTeX, 4 pages, 1 EPS figure (included)
arxiv created 1998/05/06 · openalex publication_date 1998/09/01 · arxiv updated 2009/11/30 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
The existence of a normal-state spectral gap in underdoped cuprates raises important questions about the associated superconducting phase. For example, how does this pseudogap evolve into its below Tc counterpart? In this paper we characterize this unusual superconductor by investigating the nature of the ``residual'' pseudogap below Tc, and find that it leads to an important distinction between the superconducting excitation gap and order parameter. Our approach is based on a conserving diagrammatic BCS Bose-Einstein crossover theory which yields the precise BCS result in weak coupling at any T<Tc and reproduces Leggett's results in the T=0 limit. We explore the resulting experimental implications.