Interplay between charge correlations and superconductivity across the superconducting domes of CsV$_{3}$Sb$_{5-x}$Sn$_x$

Andrea N. Capa Salinas; Brenden R. Ortiz; Steven J. Gomez Alvarado; Sarah Schwarz; Ganesh Pokharel; Luca Buiarelli; Hyeonseo Harry Park; Shiyu Yuan; Roland Yin; Suchismita Sarker; Turan Birol; Stephen D. Wilson

Paper

Interplay between charge correlations and superconductivity across the superconducting domes of CsV$_{3}$Sb$_{5-x}$Sn$_x$

Abstract

The kagome metal CsV

shows an unconventional interplay between charge density wave (CDW) order and superconductivity. Tuning the band filling is known to rapidly suppress long-range CDW order and drive the formation of two superconducting ``domes" upon increasing hole concentration. Here we determine the detailed evolution of charge correlations across this phase diagram and resolve their interplay with the superconducting state. Upon light hole-doping, the suppression of a metastable

CDW state coincides with the suppression of superconducting fluctuations present in the parent CsV

compound. Continued doping suppresses long-range

CDW order, leaving remnant short-range, quasi-1D correlations that persist across the second superconducting dome. These higher temperature charge correlations are seemingly essential to the lower temperature superconducting state, as charge correlations vanish coincident with superconductivity as a function of hole-doping. A multidomain model of short-range V-V dimer formation within the kagome plane is proposed in the second superconducting dome, where rotational and translational symmetry remain locally broken even in the absence of long-range CDW order.