Formation of deeply bound ultracold LiRb molecules via photoassociation near the Li 2S${}_{1/2}$ + Rb 5P${}_{3/2}$ asymptote

Abstract

We present spectra of ultracold ${}^7$Li${}^{85}$Rb molecules in their electronic ground state formed by spontaneous decay of weakly bound photoassociated molecules. Beginning with atoms in a dual species magneto-optical trap (MOT), weakly bound molecules are formed in the 4(1) electronic state, which corresponds to the B${}^1\Pi$ state at short range. These molecules spontaneously decay to the electronic ground state and we use resonantly enhanced multiphoton ionization (REMPI) to determine the vibrational population distribution in the electronic ground states after spontaneous emission. Many of the observed lines from the spectra are consistent with transitions from the X${}^1{\Sigma }^{+}$ ground electronic state to either the B${}^1\Pi$ or D${}^1\Pi$ electronic states that have been previously observed, with levels possibly as low as X${}^1{\Sigma }^{+}$ $(v^{\prime \prime }=2)$ being populated. We do not observe decay to weakly bound vibrational levels of the X${}^1{\Sigma }^{+}$ or a${}^3{\Sigma }^{+}$ electronic states in the spectra. We also deduce a lower bound of 3900 cm${}^{-1}$ for the dissociation energy of the LiRb${}^{+}$ molecular ion.

6 pages, 4 figures

References in corpus (5)

• Reactions of ultracold alkali metal dimers
• Enhanced sensitivity to variation of the fine structure constant and m_p/m_e in diatomic molecules
• Feshbach resonances in mixtures of ultracold ${}^6$Li and ${}^{87}$Rb gases
• Crystalline phase of strongly interacting Fermi mixtures
• Feshbach resonances in an ultracold ${}^7$Li and ${}^{87}$Rb mixture

Cited by in corpus (6)

• Two-photon photoassociation spectroscopy of an ultracold heteronuclear molecule
• Short-range Photoassociation of LiRb
• The $C{}^1{\Sigma }^{+}$, $A{}^1{\Sigma }^{+}$, and $b{}^3{\Pi }_{0^{+}}$ states of LiRb
• The $d{}^3\Pi$ state of LiRb
• Genetics-based deperturbation analysis for the spin-orbit coupled ${\mathrm{A}}^1{\Sigma }^{+}$ and ${\mathrm{b}}^3{\Pi }_{0^{+}}$ states of LiRb
• Carbon-dioxide-like Skyrmion controlled by spin-orbit coupling in atomic-molecular Bose-Einstein condensates