Fig. 2: Sb L1-edge REXS reveals conjoined CDWs in CsV3Sb5.
From: Discovery of conjoined charge density waves in the kagome superconductor CsV3Sb5
a Schematic of the REXS process. The Sb 2s to 5p transition is allowed by the dipole selection rule. b X-ray fluorescence near the Sb L1-edge (4.7 keV). c, d Photon energy scans at the \({{{{{{\bf{Q}}}}}}}_{{{{{{\rm{CDW}}}}}}}^{2\times 2\times 1}=(\pm\!0.5,\,0,\,2)\) and \({{{{{{\bf{Q}}}}}}}_{{{{{{\rm{CDW}}}}}}}^{2\times 2\times 2}=(\pm\!0.5,\,0,\,2.5)\) taken at T = 10 K. Resonant peaks in the energy scan of the 2 × 2 × 2 CDW demonstrate a Sb 5p-electron assisted CDW. This resonance can be directly observed in energy-dependent L-scans shown in e. The error bars in b represent 1-standard deviation assuming Poisson counting statistics.
