Speaker
Description
In CERN’s Alpha Experiment, clouds of positrons and anti-protons are merged to produce anti-hydrogen. The issue of low antimatter yield from this experiment has been addressed by various design alternatives in past, among which a proposal to use a two-frequency ion trap is probably the newest [1]. Here I present a concept of a new experiment that takes this technology and applies it to a field of quantum simulation.
According to theoretical predictions [2], giant molecular ions trapped in an ion trap can be used to simulate high temperature superconductivity more efficiently than experiments with ultra-cold atoms in optical lattices. A practical realisation of the idea would bring a revolution in designing of super-conductive materials that can be used in super-efficient power generators, for example. However the giant molecular ions have never been observed, as low-energy electrons get lost during their production, mainly because state-of-the-art ion traps can not confine ultra-cold atomic ions and electrons at the same time.
This limitation can be overcome by a radio-frequency ion trap that operates with two frequencies at once. Stable trapping parameters in such a trap have been mathematically derived just recently by Foot et al. [3], and I am working on plans for a practical realisation of this idea. In the experiment I am designing, the ultra-low temperature mixture of ions and electrons will be produced by photo-ionisation of laser-cooled atomic ions. The electrons will attach to Rydberg levels of the atomic ions and start being exchanged with the ions in the closest neighbourhood. This process can result in the creation of giant molecular ions under certain trapping conditions. The formation of the molecular ions will be inferred from fluorescence images of the laser-cooled atomic ions.
Besides the implications to the field of condensed matter theory, the huge dipole and magnetic moments of the molecular ions could be utilised in quantum sensors of electromagnetic fields.
References
[1] Leefer, Nathan, Kai Krimmel, William Bertsche, Dmitry Budker, Joel Fajans, Ron Folman, Hartmut Häffner, and Ferdinand Schmidt-Kaler. ‘Investigation of Two-Frequency Paul Traps for Antihydrogen Production’. Hyperfine Interactions 238, no. 1 (28 December 2016): 12. https://doi.org/10.1007/s10751-016-1388-0.
[2] Lesanovsky, I., M. Müller, and P. Zoller. ‘Trap-Assisted Creation of Giant Molecules and Rydberg-Mediated Coherent Charge Transfer in a Penning Trap’. Physical Review A 79, no. 1 (14 January 2009): 010701. https://doi.org/10.1103/PhysRevA.79.010701.
[3] Foot, C. J., D. Trypogeorgos, E. Bentine, A. Gardner, and M. Keller. ‘Two-Frequency Operation of a Paul Trap to Optimise Confinement of Two Species of Ions’. International Journal of Mass Spectrometry 430 (1 July 2018): 117–25. https://doi.org/10.1016/j.ijms.2018.05.007.
