Sympathetic cooling in a mixture of diamagnetic and paramagnetic atoms

TL;DR

This paper reports the experimental realization of a hybrid trap for ultracold rubidium and ytterbium atoms, demonstrating sympathetic cooling of multiple ytterbium isotopes via elastic collisions with rubidium, and observing isotope-dependent collisional cross sections.

Contribution

The study introduces a novel hybrid trapping method combining optical and magnetic traps for ultracold atoms, enabling sympathetic cooling of multiple isotopes and revealing isotope-dependent collisional properties.

Findings

Achieved sympathetic cooling of five ytterbium isotopes

Observed strong dependence of collisional cross section on isotope mass

Demonstrated effective hybrid trapping for ultracold atom mixtures

Abstract

We have experimentally realized a hybrid trap for ultracold paramagnetic rubidium and diamagnetic ytterbium atoms by combining a bichromatic optical dipole trap for ytterbium with a Ioffe-Pritchard-type magnetic trap for rubidium. In this hybrid trap, sympathetic cooling of five different ytterbium isotopes through elastic collisions with rubidium was achieved. A strong dependence of the interspecies collisional cross section on the mass of the ytterbium isotope was observed.