Polarized cold cloud of thulium atom

TL;DR

This paper demonstrates the optical polarization and trapping of a large number of thulium atoms in a dipole trap, verifying high polarization purity, which is crucial for cooling atoms to degeneracy.

Contribution

It reports the first successful loading and polarization of a significant number of thulium atoms into a dipole trap at 532 nm with verified high polarization purity.

Findings

Achieved polarization of 3.91(26) for thulium atoms.

Loaded 6×10^5 thulium atoms into the dipole trap.

Verified atomic polarization purity using Stern-Gerlach experiment.

Abstract

Minimization of internal degrees of freedom is an important step in the cooling of atomic species to degeneracy temperature. Here, we report on the loading of 6*10^5 thulium atoms optically polarized at maximum possible magnetic quantum number mf=-4 state into dipole trap operating at 532 nm. The purity of polarizations of the atoms was experimentally verified using a Stern-Gerlach-type experiment. Experimental measured polarization of the state is 3.91(26).