Anisotropic “charge-flipping” acceleration of highly charged ions from clusters in strong optical fields

Measurement of energies of ions that result from disassembly of atomic and molecular clusters [Arₙ, $n=2000--40 000$; (N₂)ₙ, $n=50--3000$] in strong optical fields provides evidence for ``charge-flipping'' acceleration that gives rise to ions with energies in excess of the Coulombic limit. Measurements of ion spectra as a function of cluster size, and as a function of laser polarization, demonstrate different facets of charge-flipping acceleration.