Extended Data Fig. 3: Magnetic-flux-to-voltage conversion in Mn₃Ge JJ- or Cu JJ-based SQUID.

SQUID voltage V_SQUID oscillation as a function of normalized magnetic flux \({\it{\Phi }}_{SQUID}/{\it{\Phi }}_0\) for the I = +0.30 mA-biased Mn₃Ge JJ-based SQUID, taken at T = 2 K when sweeping μ₀H_⊥ up (a) and down (b). Note that we set \(A_{SQUID}^{eff}\) = 9 µm and subtract background low-order polynomial and asymmetric voltage signals are from Fig. 3f for clarity. c,d, Data equivalent to a,b but for the I = +1.15 mA-biased Cu JJ-based SQUID. Here \(A_{SQUID}^{eff}\) = 12 µm is set and background low-order polynomial voltage signals are subtracted from Fig. 4f. Unlike the Cu JJ-based SQUID, there exists a finite phase shift φ₁ + φ₂ ≈ π in the sweep-up and sweep-down \(V_{SQUID}\left( {{\it{\Phi }}_{SQUID}/{\it{\Phi }}_0} \right)\) data of the Mn₃Ge JJ-based SQUID. This implies that the rotational chirality²⁹ and ground-state phase difference of our chiral antiferromagnetic spin-triplet JJs seems to be controlled by μ₀H (see main text for details).