Glassy behavior of anisotropic magnetoresistance in the antiferromagnet Fe_1/3NbS₂

Antiferromagnets have attracted attention as candidate material for designing faster and more robust memory devices. Recent work has shown that the magnetic order in the antiferromagnet Fe_1/3NbS₂ can be switched with low current densities [1], which may be enabled by<!--EndFragment --> the coupling between the spin glass and antiferromagnetic order [2]. The coexistence of spin glass and antiferromagnetic order is often verified with magnetometry [2, 3], but rarely with transport measurements.

We show that anisotropic magnetoresistance (AMR) can probe glassy behavior in Fe_1/3NbS₂. We observe that below the spin-glass freezing temperature the AMR differs with the presence and the direction of the cooling field. We attribute such history-dependent AMR to the coupling between the antiferromagnetic and spin-glass orders, where the resistance changes with the relative orientation of antiferromagnetic order to the spin glass moments. Our observation shows the prospect of AMR as a sensitive probe of coexisting magnetic orders.

[1] N. L. Nair et al., Nat. Mater. 19, 153 (2020)

[2] E. Maniv et al., Sci. Adv. 7, 1 (2021)

[3] E. Maniv et al., Nat. Phys. 17, 525 (2021)