Nontrivial Fermi surface topology and large anomalous Hall effect in the kagome superconductor RbV3Sb5

We report the systematic investigation of the magnetoresistance and Hall resistivity of the kagome superconductor ${\mathrm{RbV}}_{3}{\mathrm{Sb}}_{5}$ single crystals. The crystals show pronounced quantum oscillations with multifrequency. Analysis of oscillations reveals the existence of three bands that have two-dimensional character and host light effective quasiparticle mass and nontrivial Berry phase. In addition, we observed a giant anomalous Hall conductivity (AHC) that reaches up to $3.3\ifmmode\times\else\texttimes\fi{}{10}^{3}\phantom{\rule{0.16em}{0ex}}{\mathrm{\ensuremath{\Omega}}}^{\ensuremath{-}1}\phantom{\rule{0.16em}{0ex}}\mathrm{c}{\mathrm{m}}^{\ensuremath{-}1}$ in ${\mathrm{RbV}}_{3}{\mathrm{Sb}}_{5}$. The temperature dependence of AHC reveals an origin that correlated with the charge-density wave order. The anomalous Hall ratio $(\ensuremath{\sim}1%)$ shows weak temperature dependence below 30 K. These results will shed information on the nature of correlated topological physics in kagome material ${\mathrm{RbV}}_{3}{\mathrm{Sb}}_{5}$.