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Title: Incommensurate charge-stripe correlations in the kagome superconductor CsV3Sb5−xSnx
Abstract

The class ofAV3Sb5(A=K, Rb, Cs) kagome metals hosts unconventional charge density wave states seemingly intertwined with their low temperature superconducting phases. The nature of the coupling between these two states and the potential presence of nearby, competing charge instabilities however remain open questions. This phenomenology is strikingly highlighted by the formation of two ‘domes’ in the superconducting transition temperature upon hole-doping CsV3Sb5. Here we track the evolution of charge correlations upon the suppression of long-range charge density wave order in the first dome and into the second of the hole-doped kagome superconductor CsV3Sb5−xSnx. Initially, hole-doping drives interlayer charge correlations to become short-ranged with their periodicity diminished along the interlayer direction. Beyond the peak of the first superconducting dome, the parent charge density wave state vanishes and incommensurate, quasi-1D charge correlations are stabilized in its place. These competing, unidirectional charge correlations demonstrate an inherent electronic rotational symmetry breaking in CsV3Sb5, and reveal a complex landscape of charge correlations within its electronic phase diagram. Our data suggest an inherent 2kfcharge instability and competing charge orders in theAV3Sb5class of kagome superconductors.

 
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NSF-PAR ID:
10434886
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
Nature Publishing Group
Date Published:
Journal Name:
npj Quantum Materials
Volume:
8
Issue:
1
ISSN:
2397-4648
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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    Acknowledgement

    This work was supported by the U.S. National Science Foundation (NSF) Award No. ECCS-1931088. S.L. and H.W.S. acknowledge the support from the Improvement of Measurement Standards and Technology for Mechanical Metrology (Grant No. 20011028) by KRISS. K.N. was supported by Basic Science Research Program (NRF-2021R11A1A01051246) through the NRF Korea funded by the Ministry of Education.

    References

    Lee, D. H.; Park, H.; Clevenger, M.; Kim, H.; Kim, C. S.; Liu, M.; Kim, G.; Song, H. W.; No, K.; Kim, S. Y.; Ko, D.-K.; Lucietto, A.; Park, H.; Lee, S., High-Performance Oxide-Based p–n Heterojunctions Integrating p-SnOx and n-InGaZnO.ACS Applied Materials & Interfaces2021,13(46), 55676-55686.

    Hautier, G.; Miglio, A.; Ceder, G.; Rignanese, G.-M.; Gonze, X., Identification and design principles of low hole effective mass p-type transparent conducting oxides.Nat Commun2013,4.

    Yim, K.; Youn, Y.; Lee, M.; Yoo, D.; Lee, J.; Cho, S. H.; Han, S., Computational discovery of p-type transparent oxide semiconductors using hydrogen descriptor.npj Computational Materials2018,4(1), 17.

    Figure 1

     

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