Nonreciprocal impurity scattering as a probe for pairing symmetries in kagome superconductors
Abstract
The superconducting (SC) pairing symmetry and its link to time-reversal symmetry breaking (TRSB) in the vanadium-based kagome superconductors remain unresolved, with ambiguities stemming from sublattice interference and charge-density-wave (CDW) entanglement with superconductivity. Using two representative SC pairings, i.e., the conventional on-site s-wave and the TRSB dx2−y2+idxy-wave, as a model study, we theoretically show that while single magnetic impurity yield qualitatively identical spectral behavior of local density of states (LDOS) for these two symmetries, two magnetic impurities give rise to distinct LDOS patterns. For the conventional on-site s-wave pairing, time-reversal symmetry (TRS) enforces equivalent forward and backward scattering between two impurities across all impurity configurations, leading to near disappearance of a Yu-Shiba-Rusinov (YSR) state pair along the line connecting the two impurities. However, for the TRSB dx2−y2+idxy-wave pairing, this scattering equivalence holds only for inversion-symmetric impurity configurations, with a pair of YSR disappearance restricted to this case. These distinct spectral features are resolvable in scanning tunneling microscopy (STM) experiments, providing a direct avenue to discriminate TRSB and non-TRSB SC pairing symmetries in kagome superconductors and an alternative method to probe SC nonreciprocity that circumvents the ambiguities of conventional critical current-based techniques.
Versions
Related
- Impurity-dependent quantum geometry in 2D flat band superconductors
- Nonreciprocal charge transport in quantum materials: From superconductors to magnetic systems
- Probing the pairing symmetry of moiré graphene superconductors
- Competing regimes of charge-carrier and impurity scattering limiting phonon heat conduction in heavily-doped silicon
- Quantum geometry of collective pairing fluctuations in the superfluid weight of multiband superconductors
BibTeX
@misc{jiang2026nonreciprocal,
title = {{Nonreciprocal impurity scattering as a probe for pairing symmetries in kagome superconductors}},
author = {Hong-Min Jiang and Hao Du and Shun-Li Yu},
howpublished = {arXiv},
year = {2026},
month = may,
doi = {10.48550/arxiv.2605.16943},
eprint = {2605.16943},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2605.16943},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Nonreciprocal impurity scattering as a probe for pairing symmetries in kagome superconductors
AU - Hong-Min Jiang
AU - Hao Du
AU - Shun-Li Yu
PY - 2026
DA - 2026/05/16
PB - arXiv
DO - 10.48550/arxiv.2605.16943
UR - https://arxiv.org/abs/2605.16943
AB - The superconducting (SC) pairing symmetry and its link to time-reversal symmetry breaking (TRSB) in the vanadium-based kagome superconductors remain unresolved, with ambiguities stemming from sublattice interference and charge-density-wave (CDW) entanglement with superconductivity. Using two representative SC pairings, i.e., the conventional on-site s-wave and the TRSB d_x^2−y^2+id_xy-wave, as a model study, we theoretically show that while single magnetic impurity yield qualitatively identical spectral behavior of local density of states (LDOS) for these two symmetries, two magnetic impurities give rise to distinct LDOS patterns. For the conventional on-site s-wave pairing, time-reversal symmetry (TRS) enforces equivalent forward and backward scattering between two impurities across all impurity configurations, leading to near disappearance of a Yu-Shiba-Rusinov (YSR) state pair along the line connecting the two impurities. However, for the TRSB d_x^2−y^2+id_xy-wave pairing, this scattering equivalence holds only for inversion-symmetric impurity configurations, with a pair of YSR disappearance restricted to this case. These distinct spectral features are resolvable in scanning tunneling microscopy (STM) experiments, providing a direct avenue to discriminate TRSB and non-TRSB SC pairing symmetries in kagome superconductors and an alternative method to probe SC nonreciprocity that circumvents the ambiguities of conventional critical current-based techniques.
ER -