Associative ionization in a dilute ultracold ${}^7$Li gas probed with a hybrid trap

The formation of Li${}_2^{+}$ and subsequently Li${}^{+}$ ions, during the excitation of ${}^7$Li atoms to the $3S_{1\mathrm{/}2}$ state in a ${}^7$Li magneto optical trap (MOT), is probed in an ion-atom hybrid trap. Associative ionization occurs during the collision of Li($2P_{3\mathrm{/}2}$) and Li($3S_{1\mathrm{/}2}$) ultracold atoms, creating Li${}_2^{+}$ ions. Photodissociation of Li${}_2^{+}$ by the MOT lasers is an active channel for the conversion of Li${}_2^{+}$ to Li${}^{+}$. A fraction of the Li${}_2^{+}$ ions is long lived even in the presence of MOT light. Additionally, rapid formation of Li${}^{+}$ from Li${}_2^{+}$ in the absence of MOT light is observed. Resonant excitation of ultracold atoms, resulting in intricate molecular dynamics, reveals important processes in ultracold dilute gases.