AVS 65th International Symposium & Exhibition
    Surface Science Division Monday Sessions
       Session SS+HC+MI-MoM

Paper SS+HC+MI-MoM10
Isotope Enrichment via Non-Equilibrium Differential Condensation and Reflection using Supersonic Beam Gas-Surface Scattering

Monday, October 22, 2018, 11:20 am, Room 203C

Session: Dynamical Processes at Surfaces
Presenter: Jacob Graham, University of Chicago
Authors: J. Graham, University of Chicago
A. McMillan, University of Chicago
K. Nihill, University of Chicago
S.J. Sibener, University of Chicago
Correspondent: Click to Email
Isotopically enriched materials have a variety of uses including chemical labeling, energy, medicine, and quantum computing. To stimulate the further development of these applications, modern, efficient isotope enrichment methods are needed. Non-equilibrium supersonic beam gas-surface scattering and differential condensation is shown to be a new and broadly applicable route to isotope enrichment. This enrichment is demonstrated with 36Ar and 40Ar isotopes reflecting from low temperature condensates of argon, with differences arising in the condensation coefficient, which depend on the degree of collisional energy exchange for each isotope at the interface. The enrichment factors were found to be tunable as a function of incident beam kinetic energy. For example, 36Ar was found to be enriched relative to 40Ar in the scattered fraction by greater than a factor of two, for a seeded beam of argon in helium having incident velocity 1650 m/s. In a separate and complementary experiment under the same conditions, the amorphous argon condensate was found to be depleted in its 36Ar content, confirming this effect. This observed isotope selectivity during deposition introduces a new method for isotopic enrichment and purification as well as in-situ isotopic materials engineering.