Fig. 4
From: Resonant torsion magnetometry in anisotropic quantum materials
Crossing the antiferromagnetic phase boundary in RuCl3. Comparison of a the magnetic torque τ inferred from the bending amplitude of a Seiko cantilever and b the magnetotropic coefficient k measured with resonant torsion magnetometry of RuCl3 at T = 1.3 K. Magnetic field is applied at an angle ~10° from the honeycomb planes toward the crystallographic c axis. Both measurements probe the magnetic anisotropy between the in-plane and out-of-plane field orientations (i.e., α = ±(χ|| − χ⊥), where χ|| and χ⊥ are with respect to the honeycomb planes). The gray band highlights the field position of the suppression of long-range antiferromagnetic order. At the phase transition, the torque shows a deviation from the low-field quadratic response (blue curve), while the magnetotropic coefficient features a sharp jump
