Properties of superconductivity on the density wave background with small ungapped Fermi surface pockets

Abstract

We investigate the properties and the microscopic structure of superconductivity (SC), coexisting and sharing the common conducting band with density wave (DW). Such coexistence may take place when the nesting of the Fermi surface (FS) is not perfect, and in the DW state some quasi-particle states remain on the Fermi level and lead to the Cooper instability. The dispersion of such quasi-particle states is, in general, very different from that without DW. Therefore, the properties of SC on the DW background may strongly differ from those without DW. The upper critical field $H_{c2}$ in such a SC state increases as the system approaches the critical pressure, where the ungapped quasi-particles and superconductivity just appear, and it may considerably exceed the usual $H_{c2}$ value without DW. The SDW background strongly suppresses the singlet SC pairing, while it does not affect so much the triplet SC transition temperature. The results obtained explain the experimental observations in layered organic metals (TMTSF)${}_2$PF${}_6$ and $\alpha$-(BEDT-TTF)${}_2$KHg(SCN)${}_4$, where SC appears in the DW states under pressure and shows many unusual properties.

12 pages with 4 figures

References in corpus (14)

• Thermal Conductivity of superconducting (TMTSF)_2ClO_4: evidence for a nodeless gap
• Phase Diagram for Charge Density Waves in a Magnetic Field
• Coexistence of Superconductivity and Spin Density Wave orderings in the organic superconductor (TMTSF)_2PF_6
• Triplet superconducting pairing and density-wave instabilities in organic conductors
• Pairing Symmetry Competition in Organic Superconductors
• Microscopic theory of spin-triplet $f$-wave pairing in quasi-1D organic superconductors
• Superconductivity and Density Wave in the Quasi-One-Dimensional Systems: Renormalization Group Study
• Orbital quantization in the high magnetic field state of a charge-density-wave system
• Field-Induced Spin-Density-Wave Phases in Quasi-One-Dimensional Conductors: Theory versus Experiment
• Determination of the Fermi Velocity by Angle-dependent Periodic Orbit Resonance Measurements in the Organic Conductor alpha-(BEDT-TTF)2KHg(SCN)4
• Coexistence of Superconductivity and Antiferromagnetism Probed by Simultaneous NMR and Electrical Transport in (TMTSF)2PF6
• Superconductivity in the charge-density-wave state of the organic metal α-(BEDT-TTF)2KHg(SCN)4
• Soliton phase near antiferromagnetic quantum critical point in Q1D conductors
• Nature of superconducting state in the new phase in (TMTSF)${}_2$PF${}_6$ under pressure

Cited by in corpus (11)

• Spontaneous breaking of isotropy observed in the electronic transport of rare-earth tritellurides
• Coexistence of Superconductor and Spin-Density Wave in (TMTSF)2ClO4: Spatial Structure of the Two-phase State
• Conductivity of anisotropic inhomogeneous superconductors above critical temperature
• Bilayer splitting versus Fermi-surface warping as an origin of slow oscillations of in-plane magnetoresistance in rare-earth tritellurides
• Superconductivity on the density wave background with soliton-wall structure
• Role of Anion Ordering in the Coexistence of Spin-Density-Wave and Superconductivity in (TMTSF)2ClO4
• Anisotropic zero-resistance onset in organic superconductors
• Evolution of shape and volume fraction of superconducting domains with temperature and anion disorder in (TMTSF)${}_2$ClO${}_4$
• On the size of superconducting islands on the density-wave background in organic metals
• First-order phase transition between superconductivity and charge/spin-density wave as the reason of their coexistence in organic metals
• Conductivity anisotropy helps to reveal the microscopic structure of a density wave at imperfect nesting