Interplay between chiral charge density wave and superconductivity in kagome superconductors studied by self-consistent mean-field theory

Inspired by the recent discovery of a successive evolutions of electronically ordered states in the vanadium-based kagome superconductors, we present a self-consistent theoretical analysis that treats the interactions responsible for the chiral charge order and superconductivity on an equal footing. It is revealed that the self-consistent theory captures the essential features of the successive temperature evolutions of the electronic states from the high-temperature "triple-$Q$" $2\times 2$ charge-density-wave state to the nematic charge-density-wave phase, and finally to the low-temperature superconducting state coexisting with the nematic charge density wave. We provide a comprehensive explanation for the temperature evolutions of the charge ordered states and discuss the consequences of the intertwining of the superconductivity with the nematic charge density wave. Our findings not only account for the successive temperature evolutions of the ordered electronic states discovered in experiments but also provide a natural explanation for the twofold rotational symmetry observed in both the charge-density-wave and superconducting states. Moreover, the intertwining of the superconductivity with the nematic charge-density-wave order may also be an advisable candidate to reconcile the divergent or seemingly contradictory experimental outcomes regarding the superconducting properties.