fig3

Figure 3. (A) A color map of critical current in the plane of magnetic field at 2 K, and a color bar shows the value of dV/dI. An apparent current asymmetry with respect to the magnetic field can be observed. The critical current can be extracted, as shown in (C); (B) A magnification of (A). The red dotted line marks the zero-field position; (C) Nonreciprocal critical current (I_c) as a function of B_z, with positive bias (orange) and negative bias (red), exhibiting symmetry across reflection about B_z = 0. The critical current peaks at a nonzero |B_zmax| = 0.2 mT, indicated by labeled orange and blue arrows.