Mass selective laser cooling of 229 Th 3+ in a multisectional linear Paul trap loaded with a mixture of thorium isotopes

Abstract

We consider an experiment on trapping and laser cooling of ²²⁹Th³⁺ ions in a linear Paul trap in the presence of undesirable impurities such as ions of the radioactive isotope ²²⁸Th³⁺. We suggest a method of separating these impurities by means of selective laser cooling utilizing the isotope shift of cooling transitions in ²²⁹Th³⁺ and ²²⁸Th³⁺ ions. According to our estimation, the isotope shift is equal to 3.4 GHZ and makes laser separation of these isotopes possible.

Keywords

Frequency standards optical clocks laser cooling thorium nuclear transition ion trap isotope shift isotope separation

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