Fig. 3: Near-field photocurrent imaging of superconducting transport using BOSON.

a Schematic of near-field photocurrent nanoscopy, where localized optical excitation perturbs Cooper-pair transport and current redistribution in a superconducting device. b Temperature-dependent near-field photocurrent maps across the superconducting transition in a Nb device, revealing the emergence and evolution of spatially inhomogeneous local superconductor transition edges at the nanoscale