Giant Hall Resistivity and Magnetoresistance in Cubic Chiral Antiferromagnet EuPtSi

Abstract

EuPtSi crystallizes in the cubic chiral structure (P213, No. 198), which is the same as the non-centrosymmetric space group of MnSi with the skyrmion structure, and orders antiferromagnetically below a Néel temperature TN = 4.05 K. The magnetization at 2 K for the [111] direction indicates two metamagnetic transitions at the magnetic fields HA1 = 9.2 kOe and HA2 = 13.8 kOe and saturates above Hc = 26.6 kOe. The present magnetic phase between HA1 and HA2 is most likely closed in the \((H,T)\) phase and is observed in a wide temperature range from 3.6 to 0.5 K. In this magnetic phase known as the A-phase, we found giant additional Hall resistivity ΔρH(H) and magnetoresistance Δρ(H), reaching ΔρH(H) = 0.12 µΩ·cm and Δρ(H) = 1.4 µΩ·cm, respectively. These findings are obtained for H || [111] and [100], but not for H || [110] and [112], revealing an anisotropic behavior in the new material EuPtSi.