The magnetic susceptibility bifurcation in the Ni-doped Sb₂Te₃ topological insulator with antiferromagnetic order accompanied by weak ferromagnetic alignment

Shiu-Ming Huang¹, Pin Ching Wang^1*, Hao-Lun Jian³, Mitch M. C. Chou³

¹物理學系, 國立中山大學, 高雄市, Taiwan
²物理學系, 國立中山大學, 高雄市, Taiwan
³材料與光電科學學系, 國立中山大學, 高雄市, Taiwan
⁴材料與光電科學學系, 國立中山大學, 高雄市, Taiwan

* Presenter:Pin Ching Wang, email:x8506164@gmail.com

The magnetic susceptibility reveals a discontinuity at Néel temperature and a hysteresis loop with low coercive field was observed below Neel temperature. The magnetic susceptibility of zero field cool and field cool processes coincide at temperature above the discontinuity, and they split at temperature blow the discontinuity. The magnetic susceptibility splitting is larger at lower external magnetic fields. No more magnetic susceptibility splitting was observed at magnetic field above 7000 Oe that is consistent with the magnetic anisotropy energy. Our study supports that these magnetic susceptibility characteristics originates from an antiferromagnetic order accompanied by weak ferromagnetism.

Keywords: antiferromagnetism, ferromagnetism, topological material, magnetic susceptibility, Curie-Weiss law