Room temperature buffer gas beam of metastable state titanium atoms

Abstract

We produce beams of neutral titanium (Ti) atoms in their metastable $3d^{3}(^4F){4}s$ $a^5F_5$ state by laser ablation into He, N$_2$, and Ar buffer gases. The high temperatures realized in the ablation process populate the $a^5F_5$ level without the need for optical pumping. Remarkably, we observe that Ti atoms in the $a^5F_5$ state survive $1000$'s of collisions with He and Ar buffer gas atoms without being quenched to lower-energy states. We study the yield of Ti atoms when ablated into buffer gases of varying species and pressure, quantify quenching rates and diffusion cross sections based on simple models, and provide insight into optimal design parameters for an ablation cell. Using a $3.3\,$cm ablation cell with interchangeable exit apertures, we produce metastable atom beams and quantify their brilliance and velocity distributions as functions of buffer gas pressure.