2024/12/06 by KeYuan Ma, Igor Plokhikh, Ma, KeYuan +37 · 1 citation
Engineering · Materials Science · Physics and Astronomy · #FOS: Physical sciences #Iron-based superconductors research #Materials Science (cond-mat.mtrl-sci) #Rare-earth and actinide compounds #Superconducting Materials and Applications #Superconductivity (cond-mat.supr-con)
paper · pdf · doi:10.48550/arxiv.2412.05459
openalex publication_date 2024/12/06 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
The interplay between superconductivity and charge order is a central focus in condensed matter research, with kagome lattice systems offering unique insights. The kagome superconductor LaRu3Si2 (T\rm c ≃ 6.5 K) exhibits a hierarchy of charge order transitions: primary (T\rm co,I ≃ 400 K), secondary (T\rm co,II ≃ 80 K), and an additional transition at (T* ≃ 35 K). The transitions at T\rm co,II and T* are linked to electronic and magnetic responses as revealed by muon-spin rotation and magnetotransport experiments. However, the connection between superconductivity, charge order, and electronic responses has remained elusive. By employing magnetotransport and X-ray diffraction techniques under pressures of up to 40 GPa, we observe that T\rm c rises to 9 K at 2 GPa, remains nearly constant up to 12 GPa, and then decreases to 2 K at 40 GPa, resulting in a dome-shaped phase diagram. The resistivity anomaly at T* and magnetoresistance also exhibit a similar dome-shaped pressure dependence. Furthermore, we find that charge order transitions from long-range to short-range above 12 GPa, correlating with the suppression of T\rm c, suggesting superconductivity is closely tied to the charge-ordered state. Specifically, T\rm c peaks when charge order and the normal-state electronic responses are optimized. In contrast to systems like the cuprates, transition metal dichalcogenides, and other kagome materials, where superconductivity typically competes with charge order, LaRu3Si2 displays a pronounced interdependence between these two phenomena. This distinctive behavior sheds new light on the connection between superconductivity and charge order, offering avenues for theoretical advancements in understanding superconductivity.