English

Charge orders with distinct magnetic response in a prototypical kagome superconductor LaRu$_{3}$Si$_{2}$

Superconductivity 2024-03-01 v2 Materials Science

Abstract

The kagome lattice has emerged as a promising platform for hosting unconventional chiral charge order at high temperatures. Notably, in LaRu3_{3}Si2_{2}, a room-temperature charge-ordered state with a propagation vector of (14\frac{1}{4},~0,~0) has been recently identified. However, understanding the interplay between this charge order and superconductivity, particularly with respect to time-reversal-symmetry breaking, remains elusive. In this study, we employ single crystal X-ray diffraction, magnetotransport, and muon-spin rotation experiments to investigate the charge order and its electronic and magnetic responses in LaRu3_{3}Si2_{2} across a wide temperature range down to the superconducting state. Our findings reveal the emergence of a charge order with a propagation vector of (16\frac{1}{6},~0,~0) below TCO,2T_{\rm CO,2} {\simeq} 80 K, coexisting with the previously identified room-temperature primary charge order (14\frac{1}{4},~0,~0). The primary charge-ordered state exhibits zero magnetoresistance. In contrast, the appearance of the secondary charge order at TCO,2T_{\rm CO,2} is accompanied by a notable magnetoresistance response and a pronounced temperature-dependent Hall effect, which experiences a sign reversal, switching from positive to negative below TT^{*} {\simeq} 35 K. Intriguingly, we observe an enhancement in the internal field width sensed by the muon ensemble below TT^{*} {\simeq} 35 K. Moreover, the muon spin relaxation rate exhibits a substantial increase upon the application of an external magnetic field below TCO,2T_{\rm CO,2} {\simeq} 80 K. Our results highlight the coexistence of two distinct types of charge order in LaRu3_{3}Si2_{2} within the correlated kagome lattice, namely a non-magnetic charge order (14\frac{1}{4},~0,~0) below Tco,1T_{\rm co,1} {\simeq} 400 K and a time-reversal-symmetry-breaking charge order below TCO,2T_{\rm CO,2}.

Keywords

Cite

@article{arxiv.2402.16219,
  title  = {Charge orders with distinct magnetic response in a prototypical kagome superconductor LaRu$_{3}$Si$_{2}$},
  author = {C. Mielke and V. Sazgari and I. Plokhikh and S. Shin and H. Nakamura and J. N. Graham and J. Küspert and I. Bialo and G. Garbarino and D. Das and M. Medarde and M. Bartkowiak and S. S. Islam and R. Khasanov and H. Luetkens and M. Z. Hasan and E. Pomjakushina and J. -X. Yin and M. H. Fischer and J. Chang and T. Neupert and S. Nakatsuji and B. Wehinger and D. J. Gawryluk and Z. Guguchia},
  journal= {arXiv preprint arXiv:2402.16219},
  year   = {2024}
}

Comments

10 pages, 5 figures