Experimental study of the (4)0- short-range electronic state of the 85Rb133Cs molecule by high resolution photoassociation spectroscopy

We present the formation of ultracold (RbCs)-Rb-85-Cs-133 molecules in the (4)0(-) short-range electronic state and the measurement of the permanent electric dipole moment by high resolution photoassociation spectroscopy. With the rotationally resolved photoassociation spectra via resonance-enhanced two-photon ionization, spectral data have been extended to more vibrational levels compared to previous observations. Precise electric dipole moments are obtained by using the DC Stark effect of the photoassociation spectrum. These studies containing previously unobserved electronic states are important to understand the molecular structure and discover transition pathways for transferring ultracold atoms to deeply bound rovibrational levels of the electronic ground state. (C) 2016 Elsevier Ltd. All rights reserved.