Speaker
Description
The interplay between superconductivity and charge or spin order is a key focus in condensed matter physics, with kagome lattice systems providing unique insights [1-9]. We recently discovered that the kagome superconductor LaRu$_{3}$Si$_{2}$ ($T_{\rm c} \simeq 7$ K) exhibits a characteristic kagome band structure and a hierarchy of charge-order transitions at 400 K and 80 K, as well as an additional electronic and magnetic transition at 35 K [7,8]. Furtermore, using magnetotransport and X-ray diffraction under pressures up to 40 GPa, we find Tc peaks at 9 K (2 GPa), remains stable up to 12 GPa, and decreases to 2 K at 40 GPa, forming a dome-shaped phase diagram [9]. Similarly, both the resistivity anomaly at $T^{*}$ and the magnetoresistance exhibit a dome-shaped pressure dependence. Moreover, above 12 GPa, the charge order evolves from long-range to short-range, coinciding with the suppression of $T_{\rm c}$. These observations suggest that superconductivity is closely linked to the charge-ordered state and the electronic responses associated with $T_{\rm co,II}$ and $T^{*}$. Notably, $T_{\rm c}$ reaches its maximum when the charge order remains long-range and the normal-state electronic properties are optimized. These results offer fresh insights into the relationship between superconductivity and charge order, paving the way for theoretical advancements and experimental strategies, such as uniaxial stress, to amplify lattice distortions and electronic responses in the charge-ordered state, with the potential to further enhance $T_{\rm c}$.
[1] Z. Guguchia et. al., Nature Communications 11, 559 (2020).
[2] C. Mielke III et. al., and Z. Guguchia, Nature 602, 245 (2022).
[3] Z. Guguchia et. al., Nature Communications 14, 153 (2023).
[4] Z. Guguchia et. al., NPJ Quantum Materials 8, 41 (2023).
[5] Z. Guguchia et. al., Nature Communications 14, 7796 (2023).
[6] J.N. Graham et. al., and Z. Guguchia, Nature Communications 15, 8978 (2024).
[7] I. Plokhikh et. al., and Z. Guguchia, Communications Physics 7, 182 (2024).
[8] C. Mielke III, V. Sazgari et. al., and Z. Guguchia, arXiv:2402.16219 (2024).
[9] K. Ma et. al., and Z. Guguchia, arXiv:2412.05459 (2025).
| Did you request an Invitation Letter for a Visitors Visa Application | Yes |
|---|
