Pairing correlation of the Kagome-lattice Hubbard model with the nearest-neighbor interaction

Abstract

A recently discovered family of Kagome lattice materials, $\text{A}{\mathrm{V}}_3{\mathrm{Sb}}_5$($\text{A}$= $\mathrm{K},\mathrm{Rb},\mathrm{Cs}$), has attracted great interest, especially in the debate over its dominant superconducting pairing symmetry. To explore this issue, we study the superconducting pairing behavior within the Kagome-Hubbard model through the constrained path Monte Carlo method. It is found that doping around the Dirac point generates a dominant next-nearest-neighbour-$d$ pairing symmetry driven by on-site Coulomb interaction $U$. However, when considering the nearest-neighbor interaction $V$, it may induce nearest-neighbor-$p$ pairing to become the preferred pairing symmetry. Our results provide useful information to identify the dominant superconducting pairing symmetry in $\text{A}{\mathrm{V}}_3{\mathrm{Sb}}_5$ family.