Figure 6: Size and intensity scaling of the electron yield.

(a) Number of near-cutoff electrons emitted from a single nanosphere as function of laser intensity as predicted by M³C with (red curve) and without (black curve) Coulomb interaction and corresponding experimental results (circles) for I=3.0 × 10¹³ W cm⁻². The inset compares the near-cutoff electron yield (solid curves) calculated with and without mean-field to the respective total yield (dashed curves)—note the logarithmic scale. Horizontal and vertical error bars indicate the standard deviation of the particle diameter, cf. Fig. 1, and the estimated detection efficiency (see text), respectively. (b) Same as (a) but as function of laser intensity for nanopsheres with d=400 nm. The experimental results were taken under comparable conditions. Note that only electrons with projected momenta above the threshold where counted in the experiment. The horizontal error bar indicates the estimated ±15% uncertainty of the intensity; vertical error bars for the yield are defined as in (a). We checked via the M³C data that the differences between results using projected and full momenta are insignificant for this analysis.