Vortex structure in weak to strong coupling superconductors: Crossover from BCS to BEC

Masahiko Machida, Tomio Koyama, Yoji Ohashi

Research output: Contribution to journalArticle

Abstract

High-Tc cuprate and MgB2 superconductors are recognized as intermediate or strong coupling superconductors. In such a non-weak regime, the vortex core structure is an interesting issue, since the vortex dissipation is expected to be anomalously reduced due to large level distance between localized core states. In this paper, we systematically clarify the vortex core structure based on the fermion-boson model which can cover a full coupling range from weak BCS to strong BEC superconductors. The mean-field calculations on the model reveal that the distances between the low-lying core levels expand and the low-lying states finally disappear when changing the coupling from weak BCS to strong BEC regime. This result suggests that the strong coupling makes the vortex motion non-dissipative.

Original languageEnglish
Pages (from-to)194-197
Number of pages4
JournalPhysica C: Superconductivity and its Applications
Volume445-448
Issue number1-2
DOIs
Publication statusPublished - 2006 Oct 1
Externally publishedYes

Fingerprint

Superconducting materials
crossovers
Vortex flow
vortices
Bosons
Core levels
Fermions
cuprates
bosons
dissipation
fermions

Keywords

  • BCS-BEC crossover
  • Fermion-boson model
  • Vortex core
  • Vortex dissipation

ASJC Scopus subject areas

  • Condensed Matter Physics

Cite this

Vortex structure in weak to strong coupling superconductors : Crossover from BCS to BEC. / Machida, Masahiko; Koyama, Tomio; Ohashi, Yoji.

In: Physica C: Superconductivity and its Applications, Vol. 445-448, No. 1-2, 01.10.2006, p. 194-197.

Research output: Contribution to journalArticle

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