Fig. 2: Long-ranged supercurrents through a chiral non-collinear AFM.

a,c,e, Zero-field current–voltage I–V characteristics of Nb/Mn₃Ge/Nb JJs with different edge-to-edge separations d_s = 28 (a), 80 (c) and 119 nm (e), taken above (grey) and below (red) the superconducting transition of the Nb electrodes. The black solid lines are fitting curves to determine the Josephson critical current I_c. b,d,f, Associated temperature T dependence of I_c with d_s = 28 (b), 80 (d) and 119 nm (f). The black solid lines are theoretical fits to estimate the zero-temperature I_c. g, Normal-state zero-bias resistance R_n (top) and I_c (bottom) of the JJs versus d_s. From R_n(d_s), we extract the resistance-area product of Nb/Mn₃Ge interfaces to be 1 mΩ µm² and the effective resistivity for the Mn₃Ge (40 nm)/Ru (5 nm) track to be 26 µΩ cm, using a standard transmission line (TL) theory (black line, see Supplementary Text for comparison with Hall-bar devices). h, Characteristic voltage V_c = I_cR_n as a function of d_s, from which the decay length of the Josephson coupling through the Mn₃Ge spacer is determined using an exponential decay function (black curves).