We study the Fermi surface topology of a two-dimensional electron gas (2DEG) proximitized by d-wave superconductors in a linear superconductor–normal–superconductor (SNS) Josephson junction with a \(\pi\) phase difference. Owing to nodal quasiparticles and the anisotropic gap, the d-wave case differs qualitatively from the isotropic s-wave case: the nonlocal conductance is no longer directly tied to the number of critical points on the Fermi surface. Instead, we show that the rectified conductance remains quantized at low bias and faithfully encodes the Fermi surface topology via the Euler number \(\chi _F\) . This quantized response persists even for complex or multi-pocket Fermi surfaces, establishing rectified conductance as a robust and experimentally accessible probe of Fermi surface topology in gapless superconductors.
