Tunable unconventional kagome superconductivity in charge ordered RbV3Sb5 and KV3Sb5

Z. Guguchia (), C. Mielke, D. Das, R. Gupta, J.-X. Yin, H. Liu, Q. Yin, M. H. Christensen, Z. Tu, C. Gong, N. Shumiya, Md Shafayat Hossain, Ts. Gamsakhurdashvili, M. Elender, Pengcheng Dai, A. Amato, Y. Shi, H. C. Lei, R. M. Fernandes, M. Z. Hasan, H. Luetkens () and R. Khasanov ()
Additional contact information
Z. Guguchia: Paul Scherrer Institute
C. Mielke: Paul Scherrer Institute
D. Das: Paul Scherrer Institute
R. Gupta: Paul Scherrer Institute
J.-X. Yin: Southern University of Science and Technology
H. Liu: Chinese Academy of Sciences
Q. Yin: Renmin University of China
M. H. Christensen: University of Copenhagen
Z. Tu: Renmin University of China
C. Gong: Renmin University of China
N. Shumiya: Princeton University
Md Shafayat Hossain: Princeton University
Ts. Gamsakhurdashvili: Paul Scherrer Institute
M. Elender: Paul Scherrer Institute
Pengcheng Dai: Rice University
A. Amato: Paul Scherrer Institute
Y. Shi: Chinese Academy of Sciences
H. C. Lei: Renmin University of China
R. M. Fernandes: University of Minnesota
M. Z. Hasan: Princeton University
H. Luetkens: Paul Scherrer Institute
R. Khasanov: Paul Scherrer Institute

Nature Communications, 2023, vol. 14, issue 1, 1-10

Abstract: Abstract Unconventional superconductors often feature competing orders, small superfluid density, and nodal electronic pairing. While unusual superconductivity has been proposed in the kagome metals AV3Sb5, key spectroscopic evidence has remained elusive. Here we utilize pressure-tuned and ultra-low temperature muon spin spectroscopy to uncover the unconventional nature of superconductivity in RbV3Sb5 and KV3Sb5. At ambient pressure, we observed time-reversal symmetry breaking charge order below $${T}_{{{{{{{{\rm{1}}}}}}}}}^{*}\simeq$$ T 1 * ≃ 110 K in RbV3Sb5 with an additional transition at $${T}_{{{{{{{{\rm{2}}}}}}}}}^{*}\simeq$$ T 2 * ≃ 50 K. Remarkably, the superconducting state displays a nodal energy gap and a reduced superfluid density, which can be attributed to the competition with the charge order. Upon applying pressure, the charge-order transitions are suppressed, the superfluid density increases, and the superconducting state progressively evolves from nodal to nodeless. Once optimal superconductivity is achieved, we find a superconducting pairing state that is not only fully gapped, but also spontaneously breaks time-reversal symmetry. Our results point to unprecedented tunable nodal kagome superconductivity competing with time-reversal symmetry-breaking charge order and offer unique insights into the nature of the pairing state.

Date: 2023
References: View references in EconPapers View complete reference list from CitEc
Citations:

Downloads: (external link)
https://www.nature.com/articles/s41467-022-35718-z Abstract (text/html)

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:nat:natcom:v:14:y:2023:i:1:d:10.1038_s41467-022-35718-z

Ordering information: This journal article can be ordered from
https://www.nature.com/ncomms/

DOI: 10.1038/s41467-022-35718-z

Access Statistics for this article

Nature Communications is currently edited by Nathalie Le Bot, Enda Bergin and Fiona Gillespie

More articles in Nature Communications from Nature
Bibliographic data for series maintained by Sonal Shukla () and Springer Nature Abstracting and Indexing ().