Possibility of mixed helical p-wave pairings in Sr${}_2$RuO${}_4$

Abstract

The exact nature of unconventional superconductivity in Sr${}_2$RuO${}_4$ remains a mystery. At the phenomenological level, no superconducting order parameter proposed thus far seems able to coherently account for all essential experimental signatures. Among the latter is the prominent polar Kerr effect, which implies a nonzero ac anomalous Hall conductivity. Assuming the Kerr effect is intrinsic, it can be accounted for by a bulk chiral Cooper pairing with nonzero orbital angular momentum, such as $p+ip$ or $d+id$, which, however, has difficulties in being reconciled with other experimental results. Given the situation, in this paper, we propose alternative possibilities with complex mixtures of distinct helical p-wave order parameters, namely, $A_{1u}+i{A}_{2u}$ and $B_{1u}+i{B}_{2u}$ in the group theory nomenclature. These states essentially consist of two copies of chiral p-wave pairings with opposite chirality and different pairing amplitudes, and therefore support intrinsic Hall and Kerr effects. We further show that these states exhibit salient features that may explain several other key observations in this material, including the absence of spontaneous edge current, a substantial Knight shift drop, and possibly signatures in uniaxial strain and ultrasound measurements.

arXiv commentpublished version; 5 pages, 4 figures + supplemental material

References in corpus (64)

• Paired states of fermions in two dimensions with breaking of parity and time-reversal symmetries, and the fractional quantum Hall effect
• Time-Reversal Symmetry Breaking Superconductivity in Sr2RuO4
• High Resolution Polar Kerr Effect Measurements of Sr2RuO4: Evidence for Broken Time Reversal Symmetry in the Superconducting State
• Evaluation of Spin-Triplet Superconductivity in Sr2RuO4
• Pronounced drop of ${}^{17}$O NMR Knight shift in superconducting state of Sr${}_2$RuO${}_4$
• Chiral Superconductors
• Strong Peak in $T_c$ of Sr${}_2$RuO${}_4$ Under Uniaxial Pressure
• Chiral P-Wave Order in Sr_2RuO_4
• Orbital dependent superconductivity in Sr_2RuO_4
• Quasiparticle States near the Surface and the Domain Wall in a p_x\pm i p_y-Wave Superconductor
• Upper limit on spontaneous supercurrents in Sr${}_2$RuO${}_4$
• Gap Structure of the Spin-Triplet Superconductor Sr2RuO4 Determined from the Field-Orientation Dependence of Specific Heat
• Interband proximity effect and nodes of superconducting gap in Sr2RuO4
• Limits on Superconductivity-Related Magnetization in Sr${}_2$RuO${}_4$ and PrOs${}_4$Sb${}_{12}$ from Scanning SQUID Microscopy
• Spontaneous Hall effect in chiral p-wave superconductor
• Split superconducting and time-reversal symmetry-breaking transitions, and magnetic order in Sr${}_2$RuO${}_4$ under uniaxial stress
• Reduction of the ${}^{17}$O Knight shift in the Superconducting State and the Heat-up Effect by NMR Pulses on Sr${}_2$RuO${}_4$
• Thermodynamic Evidence for a Two-Component Superconducting Order Parameter in Sr${}_2$RuO${}_4$
• Is Sr2RuO4 a Chiral P-Wave Superconductor?
• Ultrasound evidence for a two-component superconducting order parameter in Sr${}_2$RuO${}_4$
• Pairing symmetry and dominant band in Sr2RuO4
• A proposal for reconciling diverse experiments on the superconducting state in Sr2RuO4
• Stabilizing Even-Parity Chiral Superconductivity in Sr${}_2$RuO${}_4$
• First-Order Superconducting Transition of Sr2RuO4
• Knight Shift and Leading Superconducting Instability From Spin Fluctuations in Sr2RuO4
• Identifying detrimental effects for multi-orbital superconductivity - Application to Sr${}_2$RuO${}_4$
• Vertical line nodes in the superconducting gap structure of Sr2RuO4
• Evidence for even parity unconventional superconductivity in Sr${}_2$RuO${}_4$
• Intrinsic Hall effect in a multiband chiral superconductor in the absence of an external magnetic field
• Large Chern Number and Edge Currents in Sr2RuO4
• Evidence from Tunneling Spectroscopy for a Quasi-One Dimensional Origin of Superconductivity in Sr2RuO4
• Superconducting Double Transition and the Upper Critical Field Limit of Sr2RuO4 in Parallel Magnetic Fields
• High sensitivity heat capacity measurements on Sr2RuO4 under uniaxial pressure
• Superconducting order parameter of Sr${}_2$RuO${}_4$: a microscopic perspective
• Spin fluctuations in Sr2RuO4 from polarized neutron scattering: implications for superconductivity
• Reduction of the spin susceptibility in the superconducting state of Sr2RuO4 observed by polarized neutron scattering
• 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
• Superconducting Symmetries of Sr${}_2$RuO${}_4$ from First-Principles Electronic Structure
• Inhomogeneous time-reversal symmetry breaking in ${\mathrm{Sr}}_2\mathrm{Ru}{\mathrm{O}}_4$
• Identifying spin-triplet pairing in spin-orbit coupled multi-band superconductors
• Micron-scale measurements of low anisotropic strain response of local $T_c$ in Sr${}_2$RuO${}_4$
• First-principles calculations of spin-orbit effects and NMR in Sr2RuO4
• Superconducting order of ${\mathrm{Sr}}_2{\mathrm{RuO}}_4$ from a three-dimensional microscopic model
• Suppression of spontaneous currents in Sr${}_2$RuO${}_4$ by surface disorder
• Intrinsic optical dichroism in the chiral superconducting state of Sr${}_2$RuO${}_4$
• Properties of edge states in spin-triplet two-band superconductor
• Suppression of Spontaneous Supercurrents in a Chiral p-Wave Superconductor
• Theory of chiral $p$-wave superconductivity with near-nodes for Sr${}_2$RuO${}_4$
• Spin-Orbit Coupling and Symmetry of the Order Parameter in Strontium Ruthenate
• Specific-heat evidence of the first-order superconducting transition in Sr2RuO4
• Topological and edge state properties of a three-band model for Sr2RuO4
• Group-theoretic classification of superconducting states of Strontium Ruthenate
• Exotic Cooper pairing in multi-orbital models of Sr${}_2$RuO${}_4$
• Spin-orbit coupling and spin-triplet pairing symmetry in $\mathrm{S}{\mathrm{r}}_2\mathrm{Ru}{\mathrm{O}}_4$
• Superconducting pairing in Sr${}_2$RuO${}_4$ from weak to intermediate coupling
• Intrinsic ac anomalous Hall effect of nonsymmorphic chiral superconductors with an application to $\mathrm{UP}{\mathrm{t}}_3$
• Distinct reduction of Knight shift in superconducting state of Sr${}_2$RuO${}_4$ under uniaxial strain
• Spontaneous Edge Current in Higher Chirality Superconductors
• Hidden anomalous Hall effect in Sr${}_2$RuO${}_4$ with chiral superconductivity dominated by the Ru $d_{xy}$ orbital
• Inter-orbital p- and d-wave pairings between $d_{xz/yz}$ and $d_{xy}$ orbitals in Sr${}_2$RuO${}_4$
• Fluctuation-driven superconductivity in Sr${}_2$RuO${}_4$ from weak repulsive interactions
• Spontaneous magnetization in unitary superconductors with time reversal symmetry breaking
• Effects of deep superconducting gap minima and disorder on residual thermal transport in $\mathrm{S}{\mathrm{r}}_2\mathrm{Ru}{\mathrm{O}}_4$

Cited by in corpus (8)

• Superconductivity in Correlated Multi-Orbital Systems with Spin-Orbit Coupling: Coexistence of Even- and Odd-Frequency Pairing and the Case of Strontium Ruthenate
• Higher angular momentum pairing states in Sr${}_2$RuO${}_4$ in the presence of longer-range interactions
• Impact of random impurities on the anomalous Hall effect in chiral superconductors
• $T_c$ and the elastocaloric effect of Sr${}_2$RuO${}_4$ under $⟨110⟩$ uniaxial stress: no indications of transition splitting
• Multipole-fluctuation pairing mechanism of $d_{x^2-y^2}+ig$ superconductivity in Sr${}_2$RuO${}_4$
• A review of some new perspectives on the theory of superconducting Sr${}_2$RuO${}_4$
• Quantum-geometry-induced anomalous Hall effect in nonunitary superconductors and application to Sr${}_2$RuO${}_4$
• Examining the possibility of chiral superconductivity in Sr${}_2$RuO${}_4$ and other compounds via applied supercurrent