Formation of ultracold, highly polar X1Σ+ NaCs molecules

Abstract

We present photoassociation spectroscopy of ultracold NaCs molecules formed in a dual-species magneto-optical trap. Excited-state molecules are formed in states correlating to the Na(3S1/2) + Cs (6P3/2) asymptote. We assign the most prominent observed vibrational progression to the ω = 2 long range state based on a comparison with ab initio potentials. Molecules are secondarily excited before decaying to deeply bound levels of the electronic ground X1Σ+ state where they are ionized and detected by timeof-flight mass spectroscopy. © IOP Publishing Ltd and Deutsche Physikalische Gesellschaft.