biostudies-literatureRoppongi MMEXT | Japan Society for the Promotion of ScienceMEXT | Japan Science and Technology Agency (JST)MEXT | Japan Society for the Promotion of Science (JSPS)National Science Foundation (NSF)National Science FoundationMEXT | Japan Science and Technology Agency667https://www.ebi.ac.uk/biostudies/studies/S-EPMC9905511biostudies-literatureUnknown14(1)The recently discovered kagome superconductors AV₃Sb₅ (A = K, Rb, Cs) exhibit unusual charge-density-wave (CDW) orders with time-reversal and rotational symmetry breaking. One of the most crucial unresolved issues is identifying the symmetry of the superconductivity that develops inside the CDW phase. Theory predicts a variety of unconventional superconducting symmetries with sign-changing and chiral order parameters. Experimentally, however, superconducting phase information in AV₃Sb₅ is still lacking. Here we report the impurity effects in CsV₃Sb₅ using electron irradiation as a phase-sensitive probe of superconductivity. Our magnetic penetration depth measurements reveal that with increasing impurities, an anisotropic fully-gapped state changes to an isotropic full-gap state without passing through a nodal state. Furthermore, transport measurements under pressure show that the double superconducting dome in the pressure-temperature phase diagram survives against sufficient impurities. These results support that CsV₃Sb₅ is a non-chiral, anisotropic s-wave superconductor with no sign change both at ambient and under pressure.Nature communicationsBulk evidence of anisotropic s-wave pairing with no sign change in the kagome superconductor CsV₃Sb₅.PMC9905511JP18KK0375JP21H01793DMR-1906325JPMJCR19T5JP20H05869JP19H05824JP22K18683JP19H00649JP22H00105JP22K18681JP22K20349JP18H05227JP22J21896Mukasa KOgawa KIshihara KOkada KGrasset RLiu SShibauchi TTanaka YKonczykowski MRoppongi MMizukami YWilson SDUwatoko YOrtiz BRHashimoto KfalseBulk evidence of anisotropic s-wave pairing with no sign change in the kagome superconductor CsV₃Sb₅.The recently discovered kagome superconductors AV₃Sb₅ (A = K, Rb, Cs) exhibit unusual charge-density-wave (CDW) orders with time-reversal and rotational symmetry breaking. One of the most crucial unresolved issues is identifying the symmetry of the superconductivity that develops inside the CDW phase. Theory predicts a variety of unconventional superconducting symmetries with sign-changing and chiral order parameters. Experimentally, however, superconducting phase information in AV₃Sb₅ is still lacking. Here we report the impurity effects in CsV₃Sb₅ using electron irradiation as a phase-sensitive probe of superconductivity. Our magnetic penetration depth measurements reveal that with increasing impurities, an anisotropic fully-gapped state changes to an isotropic full-gap state without passing through a nodal state. Furthermore, transport measurements under pressure show that the double superconducting dome in the pressure-temperature phase diagram survives against sufficient impurities. These results support that CsV₃Sb₅ is a non-chiral, anisotropic s-wave superconductor with no sign change both at ambient and under pressure.2023-01-01T00:00:00Z2023 Feb2025-04-04T23:52:42.845Z2025-04-04T23:52:42.845ZS-EPMC99055113675057610.1038/s41467-023-36273-x