Fig. 4
From: Evidence of nematic order and nodal superconducting gap along [110] direction in RbFe2As2
Effect of a surface defect (VRb) on superconductivity. a Topographic image of a surface Rb vacancy (VRb) on type A surface (Vb = 30 mV, I = 10 pA; scale bar: 5 nm). b dI/dV spectra taken at various distances from VRb (Vb = 1.8 mV, I = 100 pA, ΔV = 50 μV, Teff = 310 mK), the tip positions are marked in panel a. Inset displays the gap bottom showing the suppression of the gap. c ZBC value of the gap bottom as function of distance from VRb; the red curve is an exponential fit, which yields a decay length of 1.41 nm. d Topographic image of a Rb vacancy on type B surface (Vb = 1.0 V, I = 10 pA; scale bar: 5 nm). e dI/dV spectra taken at various distances from VRb (Vb = 2 mV, I = 100 pA, ΔV = 50 μV, Teff = 310 mK), the tip positions are marked in panel d. f ZBC value as function of distance from VRb; red curve is an exponential fit which yields a decay length of 1.37 nm
