Large Chern Number and Edge Currents in Sr2RuO4

Abstract

We show from a weak coupling microscopic calculation that the most favored chiral superconducting order parameter in Sr2RuO4 has Chern number |C|=7. The two dominant components of this order parameter are given by sin(3 kx) + i sin(3 ky) and sin(kx) cos(ky) + i sin(ky) cos(kx) and lie in the same irreducible representation Eu of the tetragonal point group as the usually assumed gap function sin(kx) + i sin(ky). While the latter gap function leads to C=1, the two former lead to C=-7, which is also allowed for an Eu gap function since the tetragonal symmetry only fixes C modulo 4. Since it was shown that the edge currents of a |C|>1 superconductor vanish exactly in the continuum limit, and can be strongly reduced on the lattice, this form of order parameter could help resolve the conflict between experimental observation of time-reversal symmetry breaking and yet the absence of observed edge currents in Sr2RuO4.

5 pages, 2 figures; Spin-orbit-coupled three-orbital BdG calculation added; Accepted for publication in Physical Review Letters

References in corpus (23)

• Non-Abelian Anyons and Topological Quantum Computation
• High Resolution Polar Kerr Effect Measurements of Sr2RuO4: Evidence for Broken Time Reversal Symmetry in the Superconducting State
• The Order Parameter for the Superconducting Phases of UPt${}_3$
• Observation of half-height magnetization steps in Sr2RuO4
• Superconductivity in the repulsive Hubbard model: an asymptotically exact weak-coupling solution
• Chiral P-Wave Order in Sr_2RuO_4
• Hidden quasi one-dimensional superconductivity in Sr${}_2$RuO${}_4$
• Surface States, Edge Currents and the Angular Momentum of Chiral p-wave Superfluids
• Is Sr2RuO4 a Chiral P-Wave Superconductor?
• Pairing symmetry and dominant band in Sr2RuO4
• Quantum Thermal Hall Effect in a Time-Reversal-Symmetry-Broken Topological Superconductor in Two Dimensions : Approach From Bulk Calculations
• Vanishing edge currents in non-$p$-wave topological chiral superconductors
• Orbital Angular Momentum and Spectral Flow in Two Dimensional Chiral Superfluids
• Non-topological nature of the edge current in a chiral p-wave superconductor
• Current inversion at the edges of a chiral $\mathbf{p}$-wave superconductor
• Spin-triplet superconductivity in Sr2RuO4 due to orbital and spin fluctuations: Analyses by two-dimensional renormalization group theory and self-consistent vertex-correction method
• Spin Triplet Superconductivity in Sr2RuO4 due to Orbital and Spin Fluctuations: Analysis by Two-Dimensional Renormalization Group Theory
• Suppression of spontaneous currents in Sr${}_2$RuO${}_4$ by surface disorder
• Properties of edge states in spin-triplet two-band superconductor
• Suppression of Spontaneous Supercurrents in a Chiral p-Wave Superconductor
• Charge and spin collective modes in a quasi-1D model of Sr2RuO4
• Microscopic theory of tunneling spectroscopy in Sr${}_2$RuO${}_4$
• Orbital momentum of chiral superfluids and spectral asymmetry of edge states

Cited by in corpus (48)

• Majorana Fermions and Topology in Superconductors
• Chiral Superconductors
• Strong Peak in $T_c$ of Sr${}_2$RuO${}_4$ Under Uniaxial Pressure
• Unconventional Superconductivity
• Towards large-Chern-number topological phases by periodic quenching
• Spin fluctuations in Sr2RuO4 from polarized neutron scattering: implications for superconductivity
• Micron-scale measurements of low anisotropic strain response of local $T_c$ in Sr${}_2$RuO${}_4$
• Time-Reversal Invariant Superconductivity of Sr${}_2$RuO${}_4$ Revealed by Josephson Effects
• Spontaneous edge current in a small chiral superconductor with a rough surface
• Properties of skyrmions and multi-quanta vortices in chiral $p$-wave superconductors
• Possible three-dimensional nematic odd-parity superconductivity in Sr${}_2$RuO${}_4$
• Superconducting pairing in Sr${}_2$RuO${}_4$ from weak to intermediate coupling
• Harmonic Fingerprint of Unconventional Superconductivity in Twisted Bilayer Graphene
• Leggett modes and multi-band superconductivity in Sr2RuO4
• Current fluctuations in unconventional superconductor junctions with impurity scattering
• Anisotropy of magnetic interactions and symmetry of the order parameter in unconventional superconductor Sr${}_2$RuO${}_4$
• Topologically protected charge transfer along the edge of a chiral $\text{p}$-wave superconductor
• Quantum Control in Open and Periodically Driven Systems
• Spontaneous surface flux pattern in chiral p-wave superconductors - revisited
• Edge current and orbital angular momentum of chiral superfluids revisited
• Josephson effect in a multi-orbital model for Sr${}_2$RuO${}_4$
• Lattices of double-quanta vortices and chirality inversion in $p_x+i{p}_y$ superconductors
• Spontaneous Edge Current in Higher Chirality Superconductors
• Ground state angular momentum, spectral asymmetry, and topology in chiral superfluids and superconductors
• Higher angular momentum pairing states in Sr${}_2$RuO${}_4$ in the presence of longer-range interactions
• Low Temperature Thermal Hall Conductivity of a Nodal Chiral Superconductor
• Anomalous Nonlocal Conductance as a Fingerprint of Chiral Majorana Edge States
• Competition between d-wave superconductivity and magnetism in uniaxially strained Sr2RuO4
• Possibility of mixed helical p-wave pairings in Sr${}_2$RuO${}_4$
• Non-thermodynamic nature of the orbital angular momentum in neutral fermionic superfluids
• Local impedance on a rough surface of a chiral $p$-wave superconductor
• Effects of deep superconducting gap minima and disorder on residual thermal transport in $\mathrm{S}{\mathrm{r}}_2\mathrm{Ru}{\mathrm{O}}_4$
• Degeneracy between even- and odd-parity superconductivity in the quasi-1D Hubbard model and implications for Sr2RuO4
• Identification of Spin-Triplet Superconductivity through a Helical-Chiral Phase Transition in Sr${}_2$RuO${}_4$ Thin-Films
• Tunable topological states hosted by unconventional superconductors with adatoms
• Interband interference effects at the edge of a multiband chiral p-wave superconductor
• Modern Theory for the Orbital Moment in a Superconductor
• Strain-induced superconductivity in Sr2IrO4
• Evolution of the filamentary 3-Kelvin phase in Pb-Ru-Sr2RuO4 Josephson junctions
• Laser pulse probe of chirality of Cooper pairs
• Thermal Hall conductivity in the spin-triplet superconductor with broken time-reversal symmetry
• Spontaneous surface current in multi-component cubic superconductors with time-reversal symmetry breaking
• Anomalous Hall Effects in Chiral Superconductors
• Polar Kerr Effect in Multiband Spin-Orbit Coupled Superconductors
• Examining the possibility of chiral superconductivity in Sr${}_2$RuO${}_4$ and other compounds via applied supercurrent
• Pairing around a Single Dirac Point: A Unifying View of Kohn-Luttinger Superconductivity in Chern Bands, Quarter Metals, and Topological Surface States
• DC-current induced domain wall in a chiral $p$-wave superconductor
• Fingerprints of possible even-parity superconducting states in Sr${}_2$RuO${}_4$ detected by planar tunneling spectroscopy