Possible Odd-Frequency Superconductivity in Strong-Coupling Electron-Phonon Systems

Abstract

A possibility of the odd-frequency pairing in the strong-coupling electron-phonon systems is discussed. Using the Holstein-Hubbard model, we demonstrate that the anomalously soft Einstein mode with the frequency ${\omega }_{\mathrm{E}}\ll {\omega }_c$ (${\omega }_c$ is the order of the renormalized bandwidth) mediates the s-wave odd-frequency triplet pairing against the ordinary even-frequency singlet pairing. It is necessary for the emergence of the odd-frequency pairing that the pairing interaction is strongly retarded as well as the strong coupling, since the pairing interaction for the odd-frequency pairing is effective only in the diagonal scattering channel, $({\omega }_n,-{\omega }_n)\to ({\omega }_{n^{\prime }},-{\omega }_{n^{\prime }})$ with ${\omega }_{n^{\prime }}={\omega }_n\gtrsim {\omega }_{\mathrm{E}}$. Namely, the odd-frequency superconductivity is realized in the opposite limit of the original BCS theory. The Ginzburg-Landau analysis in the strong-coupling region shows that the specific-heat discontinuity and the slope of the temperature dependence of the superfluid density can be quite small as compared with the BCS values, depending on the ratio of the transition temperature $T_c$ and ${\omega }_c$.

6 pages, 7 figures, submitted to J. Phys. Soc. Jpn

References in corpus (13)

• A spin triplet supercurrent through the half-metallic ferromagnet CrO2
• Theory of the proximity effect in junctions with unconventional superconductors
• Symmetries of Pairing Correlations in Superconductor-Ferromagnet Nanostructures
• Odd-frequency pairing in normal metal/superconductor junctions
• Extremely strong-coupling superconductivity and anomalous lattice properties in the beta-pyrochlore oxide KOs2O6
• Anomalous Josephson effect in p-wave dirty junctions
• Conductance Spectroscopy of Spin-triplet Superconductors
• On stability of odd-frequency superconducting state
• Theory of pairing symmetry inside the Abrikosov vortex core
• Model for Vortex-core tunneling spectroscopy of chiral p-wave superconductors via odd-frequency pairing states
• Odd-frequency pairing in a binary mixture of bosonic and fermionic cold atoms
• Strong-coupling properties of unbalanced Eliashberg superconductors
• Cooper Pair Shape in Normal-metal/Superconductor Junctions

Cited by in corpus (32)

• Spin-polarized supercurrents for spintronics: a review of current progress
• Symmetry and Topology in Superconductors - Odd-frequency pairing and edge states -
• Odd-frequency superconductivity
• Odd-frequency superconducting pairing in one-dimensional systems
• Odd-frequency superconducting states with different types of Meissner response: Problem of coexistence
• Superconducting phenomena in systems with unconventional magnets
• On the Puzzle of Odd-Frequency Superconductivity
• Superconducting Symmetries of Sr${}_2$RuO${}_4$ from First-Principles Electronic Structure
• Superconductivity of Composite Particles in Two-Channel Kondo Lattice
• Mean-field description of odd-frequency superconductivity with staggered ordering vector
• Coexistence of Even- and Odd-Frequency Superconductivities Under Broken Time-Reversal Symmetry
• Superconductivity in Correlated Multi-Orbital Systems with Spin-Orbit Coupling: Coexistence of Even- and Odd-Frequency Pairing and the Case of Strontium Ruthenate
• Consequences of bulk odd-frequency superconducting states for the classification of Cooper pairs
• Theory of proximity effect in two-dimensional unconventional superconductor with Rashba spin-orbit interaction
• Dia- and paramagnetic Meissner effect from odd-frequency pairing in multi-orbital superconductors
• Strong-Coupling Superconductivity with Mixed Even- and Odd-Frequency Pairing
• Pairing symmetry of superconductivity coexisting with antiferromagnetism
• Emergent Odd-Frequency Superconducting Order Parameter near Boundaries in Unconventional Superconductors
• Dimensional Reduction and Odd-Frequency Pairing of the Checkerboard-Lattice Hubbard Model at 1/4-Filling
• Odd-frequency pairing inherent in Bogoliubov Fermi liquid
• Odd-frequency Berezinskii superconductivity in Dirac semimetals
• Gapped superconductivity with all symmetries in InSb (110) quantum wells in proximity to s-wave superconductor in Fulde-Ferrell-Larkin-Ovchinnikov phase or with a supercurrent
• Theory of pair density wave on a quasi-one-dimensional lattice in the Hubbard model
• Superconducting pairing symmetry on the extended Hubbard model in the presence of the Rashba-type spin-orbit coupling
• Induced odd-frequency superconducting state in vertex-corrected Eliashberg theory
• Quantum phase transition in a clean superconductor with repulsive dynamical interaction
• Mixing of odd- and even-frequency pairings in strongly correlated electron systems under magnetic field
• Impact of impurity scattering on odd-frequency spin-triplet pairing near the edge of the Kitaev chain
• Odd-frequency pairing and time-reversal symmetry breaking for repulsive interactions
• Pairing properties of an odd-frequency superfluid Fermi gas
• Odd-frequency superfluidity from a particle-number-conserving perspective
• Eight-fold classification of superconducting orders