Supercurrents and spontaneous time-reversal symmetry breaking by nonmagnetic disorder in unconventional superconductors

Breiø, Clara N.; Hirschfeld, P. J.; Andersen, Brian M.

doi:10.1103/physrevb.105.014504

Cited by 11 publications

(7 citation statements)

References 45 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…However, a more recent theory [44][45][46][47][48] has reveal that spin-orbit coupling can protect unconventional pairing states, which is also supported by experiment [49][50][51]. Moreover, disorder can even be the driving force inducing a time-reversal symmetry-breaking superconductor, which leads us to scenario (iii): As demonstrated in recent theoretical works on d-wave superconductors [52,53], when two superconducting pairing channels are in close competition, strong disorder can locally induce complex admixtures of these orders leading to local currents, even if the clean sample was in a time-reversal symmetric state. Finally, as pointed out in Ref.…”

mentioning

confidence: 73%

Time-reversal symmetry breaking in the superconducting state of ScS

Arushi

Singh

et al. 2022

Phys. Rev. B

View full text Add to dashboard Cite

We have studied the electronic properties of ScS, a transition-metal monochalcogenide with a rocksalt crystal structure, using magnetization, specific heat, transport, and muon spin rotation/relaxation (μSR) measurements. All measurements confirm the bulk superconductivity in ScS with a transition temperature of T C = 5.1(5) K. Specific heat together with transverse-field μSR measurements indicate a full gap, while our zero-field μSR study reveals the presence of spontaneous static or quasistatic magnetic fields emerging when entering the superconducting state. We discuss various possible microscopic origins of the observed time-reversal symmetry breaking. As none of them can be readily reconciled with a conventional pairing mechanism, this introduces ScS as a candidate material for unconventional superconductivity.

show abstract

mentioning

confidence: 73%

Time-reversal symmetry breaking in the superconducting state of ScS

Arushi

Singh

et al. 2022

Phys. Rev. B

View full text Add to dashboard Cite

show abstract

“…From the theoretical standpoint, while it has been proposed that highly disordered d-wave superconductors can exhibit responses consistent with a granular picture 51 a recent study searching for this effect found no significant self-organization of regions of well-defined phase. 62 It therefore seems likely that, while granular, phasefluctuation-dominated behavior may indeed exist in some overdoped samples, it is not intrinsic to cuprates, but rather due to chemical inhomogeneities that arise naturally in the growth process of some samples of some materials. In this case, the description of the somewhat idealized disorderaveraged dirty d-wave theory may indeed prove adequate for most of the overdoped phase diagram, until the falling superfluid density induces strong phase fluctuations 63 that may overcome the quasiparticle responses for some observables in samples with very small T c .…”

Section: B Electronic Inhomogeneitymentioning

confidence: 99%

Effect of realistic out-of-plane dopant potentials on the superfluid density of overdoped cuprates

U.¹,

Mishra²,

R.³

et al. 2022

Preprint

Self Cite

View full text Add to dashboard Cite

Recent experimental papers on hole-doped overdoped cuprates have argued that a series of observations showing unexpected behavior in the superconducting state imply the breakdown of the quasiparticle-based Landau-BCS paradigm in that doping range. In contrast, some of the present authors have argued that a phenomenological "dirty d-wave" theoretical analysis explains essentially all aspects of thermodynamic and transport properties in the superconducting state, provided the unusual effects of weak, out-of-plane dopant impurities are properly accounted for. Here we attempt to place this theory on a more quantitative basis by performing abinitio calculations of dopant impurity potentials for LSCO and Tl-2201. These potentials are more complex than the pointlike impurity models considered previously, and require calculation of forward scattering corrections to transport properties. Including realistic, ARPES-derived bandstructures, Fermi liquid renormalizations, and vertex corrections, we show that the theory can explain semiquantitatively the unusual superfluid density measurements of the two most studied overdoped materials.

show abstract

“…TRSB in non-chiral superconductors can be exposed, for example, near inhomogeneities. Specifically, pointlike disorder directly brings out the symmetry of the complex order parameter in localized supercurrents bound to the disorder sites [64][65][66][67]. To determine the impact of a single nonmagnetic impurity near the accidental degeneracy lines, we have solved the related real-space Bogoliubov-de Gennes equations and computed the resulting current densities between all NN and NNN bonds ).…”

Section: Momentum-dependent Gap Structuresmentioning

confidence: 99%

Revisiting superconductivity in the extended one-band Hubbard model: Pairing via spin and charge fluctuations

et al. 2022

Self Cite

View full text Add to dashboard Cite

The leading superconducting instabilities of the two-dimensional extended repulsive one-band Hubbard model within spin-fluctuation pairing theory depend sensitively on electron density, band and interaction parameters. We map out the phase diagrams within a random phase approximation (RPA) spin-and charge-fluctuation approach, and find that while B1g (d x 2 −y 2 ) and B2g (dxy) pairing dominates in the absence of repulsive longer-range Coulomb interactions VNN, the latter induces pairing in other symmetry channels, including e.g A2g (g-wave), nodal A1g (extended s-wave), or nodal Eu (p-wave) spin-triplet superconductivity. At the lowest temperatures, transition boundaries in the phase diagrams between symmetry-distinct spin-singlet orders generate complex time-reversal symmetry broken superpositions. By contrast, we find that boundaries between singlet and triplet regions are characterized by first-order transitions. Finally, motivated by recent photoemission experiments, we have determined the influence of an additional explicitly attractive nearest-neighbor interaction, VNN < 0, on the superconducting gap structure. Depending on the electronic filling, such an attraction boosts Eu (p-wave) spin-triplet or B1g (d x 2 −y 2 ) spin-singlet ordering.

show abstract

Supercurrents and spontaneous time-reversal symmetry breaking by nonmagnetic disorder in unconventional superconductors

Cited by 11 publications

References 45 publications

Time-reversal symmetry breaking in the superconducting state of ScS

Time-reversal symmetry breaking in the superconducting state of ScS

Effect of realistic out-of-plane dopant potentials on the superfluid density of overdoped cuprates

Revisiting superconductivity in the extended one-band Hubbard model: Pairing via spin and charge fluctuations

Contact Info

Product

Resources

About