Anomalous impurity effect in the heavy-fermion superconductor CeCu2Si2
Shan Zhao, Weifu Liu, Yi-feng Yang, Shiping Feng, Bin Liu
DOI 10.1103/PhysRevB.110.054512 · Physical Review B
Active bibliographic source — not scientific approval
Bibliographic access preserves source history; it does not approve extracted materials or validate reported claims. Review warnings on each occurrence separately.
Abstract
Recent observations of a contradictory impurity effect in the heavy-fermion superconductor CeCu2Si2 at ambient pressure have hindered the identification of its pairing symmetry. Here, we perform theoretical analyses with both intraband and interband impurity scatterings for the nodeless s±-wave pairing, and report an anomalous nonmonotonic variation of its Tc suppression with the scattering strength. Our results reproduce the prominent reduction of Tc in good agreement with earlier experiments by atomic substitution and explains as well its robustness against electron irradiation. We ascribe the latter to the screening of the interband impurity potential in the strong scattering or unitary region. This resolves the seeming contradiction in different experimental probes and provides an important support to the nodeless s±-wave scenario in CeCu2Si2 at ambient pressure. Our theory may be extended to other narrow-band systems such as twisted bilayer graphene and the recently discovered bilayer or trilayer nickelate superconductors, and provide a useful way to distinguish different pairing candidates thereof.
Source-reported materials — not catalogue approval
| Formula | Reported Tc (K) | Pressure (GPa) | Type |
|---|---|---|---|
| CeCu2Si2 Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula. | 0.6 | Pressure unresolved | unknown |
Similar papers
Revealing the Heavy Quasiparticles in the Heavy-Fermion Superconductor CeCu2Si2
similarity 0.96Zhongzheng Wu et al.
Source status unknown — claims are unverified
Thermodynamic study of gap structure and pair-breaking effect by magnetic field in the heavy-fermion superconductor CeCu2Si2
similarity 0.95Shunichiro Kittaka et al.
Source status unknown — claims are unverified
Superconductivity in heavy-fermion CeRh2Si2
similarity 0.95R. Movshovich et al.
Source status unknown — claims are unverified
High-resolution magnetization studies of the heavy-fermion superconductor CeCu2Si2 at very low temperatures and in high magnetic fields
similarity 0.95T. Tayama et al.
Source status unknown — claims are unverified
Multiband Superconductivity with Unexpected Deficiency of Nodal Quasiparticles in CeCu2Si2
similarity 0.95Shunichiro Kittaka et al.
Source status unknown — claims are unverified
Hydrodynamic description of collective modes in heavy-fermion superconductors
similarity 0.94J. P. Rodriguez
Source status unknown — claims are unverified