Year: 2026
Type: article
Abstract: Direct motional coupling of opposite-charge trapped-ion pairs could provide a pathway to extend ultra-low temperatures and quantum control to negative ions that lack the suitable electronic energy structures required for direct laser cooling. Because positive and negative ions cannot be confined within a single electrostatic potential well, I investigate a configuration where single ions are trapped in close proximity within separate potential wells to couple their motion. I analytically and numerically evaluate the electrostatic trapping requirements. As a concrete implementation, I present an optimized segmented surface Paul trap design to couple an antimatter hydrogen molecular ion ( H ¯ 2 − ) and a beryllium ion ( 9 Be + ). A motional coupling frequency of 5 kHz can be achieved at an ion–ion separation of 35 μ m, with an ion height of 50 μ m, axial trap frequencies of 4 MHz, and static trap voltages with a magnitude of ≈ 20 V . Finally, I outline three applications for this technique: quantum logic spectroscopy of H ¯ 2 − for matter-antimatter comparisons, the preparation of cold neutral deuterium atoms via near-threshold photo-detachment of D − for optical trapping, and quantum information processing using equal-mass opposite-charge ion pairs.
Author: Daniel Kienzler
Institution: ETH Zurich
Language: English
Subfield: Atomic and Molecular Physics, and Optics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $3,325
OpenAlex ID: W7165931405