Fermi surface of the magnetic kagome compound GdV 6 Sn 6 investigated using de Haas-van Alphen oscillations

The shape of the Fermi surface, and the cyclotron effective mass of the kagome magnet GdV 6 Sn 6 charge carriers are investigated using de Haas-van Alphen (dHvA) oscillation measurements and electronic band structure calculations. The temperature- and angle -dependent torque magnetometry measurements revealed at least nine different frequencies ranging from - 10 T up to - 9000 T. These frequencies correspond to extremal areas of the Fermi surface ranging from - 0 . 2% up to 50% of the first Brillouin zone, qualitatively consistent with the electronic band structure calculations. The angle -dependent dHvA oscillation frequencies indicate that the smaller pockets of the Fermi surface have an almost three-dimensional character whereas the bigger pockets of the Fermi surface are mostly two dimensional. We also find evidence of the presence of light [0 . 28(1) m 0 ] as well as heavy [2 . 37(18) m 0 ] charge carriers through the analysis of the temperature dependence of dominant frequencies. The comparison of the observed frequencies with the electronic band structure calculations indicates that the heavy masses correspond to saddle-point-like features of electronic band structure at the M point. The observation of the multiple low frequencies and the calculated contributions from various bands to such low frequencies prevent the estimation of the topological nature of bands containing lighter fermions. In conclusion, our work reveals the features of a Fermi surface containing enhanced mass fermions originating from saddle points in the electronic band structure at the M point, which is inherent to kagome lattices.