Fig. 1: Sample layout and DC transport measurements.
From: Giant fractional Shapiro steps in anisotropic Josephson junction arrays
a A schematic illustration, together with a false-coloured scanning electron microscopy image (of Device 1), of the superconductor-normal metal (S–N) hybrid devices studied in this work. The black scale bar corresponds with 200 nm. b The temperature, T, and DC current, IT, dependence of the Device 2 differential resistance, dVT/dIT, under a zero applied magnetic field condition. NS, VS and Z–VS indicate the normal state, voltage state and zero-voltage state of the Josephson junction array, respectively. Concerning the discontinuity of the VS-NS transitions around T = 1.8 K we refer to the Methods section-electrical characterization. c A few representative voltage, V, versus current, I, curves and d dV/dI − I curves at different temperatures for a single junction in Device 2. e The temperature dependence of the critical current, Ic, of a single junction for both Devices (red open circles for Device 2, blue open circles for Device 1) as extracted from Fig. 1b (and similar data for Device 1). The solid lines show the fit using the high temperature limit of Likharev’s theory for long diffusive SNS-junctions.
