Optical manipulation of the charge-density-wave state in RbV3Sb5

• 成果类型: Article
• 署名作者: Xing, Yuqing; Bae, Seokjin; Ritz, Ethan; Yang, Fan; Birol, Turan; Salinas, Andrea N. Capa; Ortiz, Brenden R.; Wilson, Stephen D.; Wang, Ziqiang; Fernandes, Rafael M.; Madhavan, Vidya
• 署名单位: University of Illinois System; University of Illinois Urbana-Champaign; University of Illinois System; University of Illinois Urbana-Champaign; University of Minnesota System; University of Minnesota Twin Cities; University of California System; University of California Santa Barbara; Boston College; University of Minnesota System; University of Minnesota Twin Cities
• 刊物名称: Nature
• ISSN/ISSBN: 0028-6482
• DOI: 10.1038/s41586-024-07519-5
• 发表日期: 2024-07-04
• 页码: 60-+
• 关键词: flux phase; kagome; ORDER; MODEL

摘要

Broken time-reversal symmetry in the absence of spin order indicates the presence of unusual phases such as orbital magnetism and loop currents(1-4). The recently discovered kagome superconductors AV(3)Sb(5) (where A is K, Rb or Cs)(5,6) display an exotic charge-density-wave (CDW) state and have emerged as a strong candidate for materials hosting a loop current phase. The idea that the CDW breaks time-reversal symmetry(7-14) is, however, being intensely debated due to conflicting experimental data(15-17). Here we use laser-coupled scanning tunnelling microscopy to study RbV3Sb5. By applying linearly polarized light along high-symmetry directions, we show that the relative intensities of the CDW peaks can be reversibly switched, implying a substantial electro-striction response, indicative of strong nonlinear electron-phonon coupling. A similar CDW intensity switching is observed with perpendicular magnetic fields, which implies an unusual piezo-magnetic response that, in turn, requires time-reversal symmetry breaking. We show that the simplest CDW that satisfies these constraints is an out-of-phase combination of bond charge order and loop currents that we dub a congruent CDW flux phase. Our laser scanning tunnelling microscopy data open the door to the possibility of dynamic optical control of complex quantum phenomenon in correlated materials.