Scientists Achieve Coulomb Crystallization of Xenon Highly Charged Ions in Laser-Cooled Calcium Matrix
Researchers successfully cooled and crystallized xenon highly charged ions (HCIs) by embedding them within laser-cooled calcium ion crystals in a Paul trap, creating mixed-species crystal structures. The work combines established quantum control techniques for calcium ions with the complex atomic properties of xenon HCIs. The achievement opens new possibilities for optical frequency metrology, fundamental physics searches, and quantum information applications.
An international team of physicists has demonstrated sympathetic cooling and Coulomb crystallization of xenon highly charged ions by trapping them alongside laser-cooled calcium-40 ions in a cryogenic linear Paul trap. The xenon HCIs are produced in a compact electron beam ion trap, then charge-selected, decelerated, and injected into the trap where they become embedded within calcium ion Coulomb crystals, appearing as dark voids in fluorescence images. By carefully controlling the number of trapped ions, the researchers created mixed-species crystal arrangements with arbitrary ordering patterns and investigated xenon-calcium ion strings to confirm charge states, measure HCI lifetimes, and characterize the motional modes of the mixed-species system. This platform effectively merges the well-established quantum control capabilities developed for calcium ions with the rich atomic physics properties of xenon highly charged ions, creating a versatile system for precision spectroscopy, tests of fundamental physics, and quantum computing applications.
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- arXiv physicsCenter
Coulomb crystallization of xenon highly charged ions in a laser-cooled Ca+ matrix
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