Nonlinear stopping of heavy clusters in matter: A case study

When impacting on a solid, heavy cluster atoms are stopped less then equi-velocity atoms. Using molecular-dynamics simulation, we study this so-called clearing-the-way effect systematically for the exemplary case of Aun clusters (n = 1–402) bombarding a solid Ar target with energies in the range of Eat = 10–1000 eV/atom. We find that cluster stopping is reduced by a factor n−β with respect to that of equi-velocity atoms. The exponent β decreases from 0.46 at Eat = 10 eV/atom to 0.17 at Eat = 1000 eV/atom.