Fig. 3

Kondo screening of the hcp hollow cluster. a Colored lines are spectra taken at the indicated magnetic fields on the hcp hollow cluster (T = 0.3 K). The black lines are fits to the sum of two Fano-functions (values of the full width at half maximum Γ≈0.5 meV and of the form factor q, see Supplementary Note 3, Supplementary Table 3, and Supplementary Fig. 6). b Symbols are the magnetic field dependent energetic positions of the Kondo resonances extracted from the fitted Fano-functions in a. The solid lines are linear fits through (E _i ,B) = (0,0) resulting in the g-factors of 1.46 and 1.91 for the positive and negative energy side, respectively. c Measured temperature dependence of the Kondo resonance (colored lines, B = 0T), together with fitted single Fano-functions (black lines, E _i  ≈ 0 meV, values of q, see Supplementary Table 4). d Temperature dependency of the width Γ of the Kondo resonance extracted from the fitted Fano-functions in c, together with a fit to a power law (gray line) and to numerical renormalization group calculations for a spin-1/2 impurity in the strong coupling regime (gray dots, taken from ref. ⁴⁰)