Fig. 2: Temperature-dependent dI/dV spectra of RhPb2 without/with proximal superconductor Pb.
From: Anomalous superconducting proximity effect of planar Pb–RhPb2 heterojunctions in the clean limit
a, b Normalized dI/dV spectra (setpoint: V = 3 mV, I = 500 pA) on i- and p-RhPb2 at 0.4 K, respectively. The colored lines show the best fits of the experimental data (empty circles) to the Dynes model with isotropic (blue dashed lines) and anisotropic (red solid lines) s-wave gap functions. Insets show the polar plot of the superconducting gap Δ as a function of θ. The normalization was performed by dividing the raw tunneling dI/dV spectra by their backgrounds, extracted from a linear fit to the conductance beyond the superconducting gaps. c, d Dependence of dI/dV spectra on temperature as indicated on both i- and p-RhPb2, respectively. The red lines describe the best fits to anisotropic s-wave gap functions. The spectra have been offset vertically on the dI/dV intensity axis for clarity. e, f Temperature-dependent superconducting gap parameters of Δ (red), the isotropic component Δ1 (brown) and anisotropic component Δ2 (cyan) on i- and p-RhPb2 films, respectively. Solid lines represent the fitting by the BCS gap function.
