Superconductivity above a quantum critical point in a metal -- gap closing vs gap filling, Fermi arcs, and pseudogap behavior

Abstract

We consider a quantum-critical metal with interaction mediated by fluctuations of a critical order parameter. This interaction gives rise to two competing tendencies -- pairing and non-Fermi liquid behavior. Due to competition, the pairing develops below a finite $T_p$, however its prominent feedback on the fermionic self-energy develops only at a lower $T_{cross}$. At $T<T_{cross}$ the system behavior is similar to that of a BCS supercoductor -- the density of states (DOS) and the spectral function (SF) have sharp gaps which close as $T$ increases. At higher $T_{cross}<T<T_p$ the DOS has a dip, which {\it fills in} with increasing $T$. The SF in this region shows either the same behavior as the DOS, or has a peak at $\omega =0$ (the Fermi arc), depending on the position on the Fermi surface. We argue that phase fluctuations are strong in this $T$ range, and the actual $T_c\sim T_{cross}$, while $T_p$ marks the onset of pseugogap behavior. We compare our theory with the behavior of optimally doped cuprates.

6 pages, 3 figures, submitted to PRL

References in corpus (26)

• Scanning tunneling spectroscopy of high-temperature superconductors
• Strong electronic correlations from Hund's coupling
• Quantum phase transitions of metals in two spatial dimensions: II. Spin density wave order
• Low energy effective theory of Fermi surface coupled with U(1) gauge field in 2+1 dimensions
• Energy gaps in high-transition temperature cuprate superconductors
• From a single-band metal to a high-temperature superconductor via two thermal phase transitions
• From a single-band metal to a high-temperature superconductor via two thermal phase transitions (Supporting Material)
• Enhancement of superconductivity near a nematic quantum critical point
• Are non-Fermi-liquids stable to Cooper pairing?
• Strongly Correlated Superconductivity: a plaquette Dynamical mean field theory study
• Evidence for unusual superconducting correlations coexisting with stripe order in La(1.875)Ba(0.125)CuO(4)
• A Systematic Study of Electron-Phonon Coupling to Oxygen Modes Across the Cuprates
• Protected nodes and the collapse of the Fermi arcs in high Tc cuprates
• Pseudogap from ARPES experiment: three gaps in cuprates and topological superconductivity
• Competition between spin density wave order and superconductivity in the underdoped cuprates
• The Origin and Non-quasiparticle Nature of Fermi Arcs in Bi${}_2$Sr${}_2$CaCu${}_2$O${}_{8+\delta }$
• Gap anisotropy and universal pairing scale in a spin fluctuation model for cuprates
• Gapless superconductivity and the Fermi arc in the cuprates
• Quantum critical properties of a metallic spin density wave transition
• Feedback of superconducting fluctuations on charge order in the underdoped cuprates
• Magneto-optical signatures of a cascade of transitions in La${}_2-x$Ba${}_x$CuO${}_4$
• Pre-pairing and the "Filling" Gap in the Cuprates From the Tomographic Density of States
• The special role of the first Matsubara frequency for superconductivity near a quantum-critical point -- the non-linear gap equation below $T_c$ and spectral properties in real frequencies
• Insensitivity of superconductivity to disorder in the cuprates
• A reevaluation of the coupling to a bosonic mode of the charge carriers in (Bi,Pb)${}_2$Sr${}_2$CaCu${}_2$O${}_{8+\delta }$ at the antinodal point
• Temperature dependent Fermi arcs in the normal state of the underdoped cuprate superconductors

Cited by in corpus (7)

• Eliashberg equations for an electron-phonon version of the Sachdev-Ye-Kitaev model: Pair Breaking in non-Fermi liquid superconductors
• Interplay between superconductivity and non-Fermi liquid at a quantum critical point in a metal. II. The $\gamma$-model at a finite $T$ for $0<\gamma <1$
• Interplay between superconductivity and non-Fermi liquid at a quantum-critical point in a metal: V. The $\gamma$ model and its phase diagram. The case $\gamma =2$
• Superconductivity of incoherent electrons in Yukawa-SYK model
• Interplay between superconductivity and non-Fermi liquid at a quantum-critical point in a metal. III: The $\gamma$ model and its phase diagram across $\gamma =1$
• Superconductivity with and without glue and the role of the double-occupancy forbidding constraint in the t-J-V model
• Critical current density of hole doped high-Tc cuprates and heavy fermion superconductors: relevance to the possible quantum critical behavior