Magneto-transport properties and Fermi surface topology in Weyl semimetal EuAuSb

We report a comprehensive investigation of the magneto-transport properties of hexagonal Weyl semimetal EuAuSb. Our findings show EuAuSb has an antiferromagnetic (AFM) ordering temperature, T_N, of 3.90 K in both temperature dependent magnetic susceptibility and resistivity measurements. Below T_N, we observed hysteresis in the magnetic field dependent longitudinal magnetoresistance (LMR), suggesting a complex magnetic ordering or metamagnetism. Additionally, we observed a giant total Hall angle and topological Hall effect. At low temperatures, two quantum oscillation frequencies in LMR were observed, likely resulting from large Zeeman splitting in the ferromagnetic (FM) polarization state. As the temperature increases, these frequencies merge as the system transitions into paramagnetic state, accompanied by the chiral magnetic effect (CME), evidenced by the large negative LMR in parallel electric and magnetic fields.