Seminar “Nuclear Theory”

Date and Time: Monday, 15 March 2021, at 3:30 PM

Venue: Online conference on Zoom, Bogoliubov Laboratory of Theoretical Physics

Seminar topic: «A new mechanism for sympathetic cooling of atoms and ions in atomic and ion-atomic traps»

Speaker: V. S. Melezhik

Abstract:

Sympathetic cooling of a Fermi gas with a buffer gas of bosonic atoms is an effective way to achieve quantum degeneracy in Fermi systems. However, all attempts to use this method for cooling ions until recently were ineffective because of the unremovable ion “micromotion” in electromagnetic Paul traps, which prevents the realization of a number of urgent projects with cold atom-ion systems. In this regard, we propose a new efficient method for sympathetic cooling of ions: the use for this purpose of cold buffer atoms in the region of atom-ion confinement-induced resonances (CIRs). The sympathetic cooling of ions near the confinement-induced resonances (CIR) is investigated within the framework of the quantum-quasiclassical approach using the example of Li-Yb+ and Li-Yb systems confined in atom-ion and atomic traps, respectively. It is shown that an atom-ion pair near CIR reproduces the collisional dynamics of a pair of noninteracting fermions. This prevents the complete approach of the atom with the ion in a collision and does not enhance the “micromotion” of the ion, which interferes with its sympathetic cooling.