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Demonstration of magnetically activated and guided isotope separation


Enriched isotopes are widely used in medicine, basic science and energy production, and the need will only grow in the future. The main method for enriching stable isotopes today, the calutron, dates back over eighty years and has an uncertain future, creating an urgent need, especially in nuclear medicine. We report here the experimental realization of a general and efficient method for isotope separation that presents a viable alternative to the calutron. Combining optical pumping and a unique magnet geometry, we observe substantial depletion of Li-6 throughput in a lithium atomic beam produced by an evaporation source over a range of flux. These results demonstrate the viability of our method to yield large degrees of enrichment in a manner that is amenable to industrial scale-up and the production of commercially relevant quantities.

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Figure 1: Schematic top-down view of apparatus used for lithium separation.
Figure 2: Effect of source position on the profile of lithium throughput.
Figure 3: Isotope-selective measurements.
Figure 4: Throughput and efficiency measurements.


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The authors would like to thank K. Melin for his contributions to the experiment.

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T.R.M., B.K. and M.G.R. contributed equally to the experiment. All authors discussed the results and commented on the manuscript.

Corresponding author

Correspondence to Mark G. Raizen.

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The authors declare no competing financial interests.

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Mazur, T., Klappauf, B. & Raizen, M. Demonstration of magnetically activated and guided isotope separation. Nature Phys 10, 601–605 (2014).

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