Isotope separation and enrichment by ultrafast laser ablation

Spatial separation of isotopes in ultrafast laser ablation plumes is observed for a variety of elements in the periodic table. Observations are made with a charge-state discriminating mass analyzer as a function of angle relative to the center of the ablation plume. Data is presented for femtosecond and picosecond laser pulses showing enrichments by factors of 2 to 20 depending on element, charge state, and laser pulse duration. Thin films are deposited from the plasma plumes, as a function of distance from the ablation source, and used to record the spatial distribution of isotopes. This information is utilized to construct a model for the isotopic separation process and to infer characteristics of the electromagnetic fields in the ablation plasmas.