Two-photon photoassociation spectroscopy of the Σ+2 YbLi molecular ground state

Abstract

We report on measurements of the binding energies of several weakly bound vibrational states of the paramagnetic 174 Yb 6 Li molecule in the electronic ground state using two-photon spectroscopy in an ultracold atomic mixture confined in an optical dipole trap. We theoretically analyze the experimental spectrum to obtain an accurate description of the long-range potential of the ground state molecule. Based on the measured binding energies, we arrive at an improved value of the interspecies s-wave scattering length as0 = 30 a0. Employing coherent two-photon spectroscopy we also observe the creation of "dark" atom-molecule superposition states in the heteronuclear Yb-Li system. This work is an important step towards the efficient production of ultracold YbLi molecules via association from an ultracold atomic mixture.

Feshbach Resonances in p -Wave Three-Body Recombination within Fermi-Fermi Mixtures of Open-Shell Li6 and Closed-Shell Green1, Li2, Toh3 et al. 2020Phys. Rev. XSelf Cite541270View full textAdd to dashboardCite

“…The observations confirm the accuracy of the single interatomic potential controlling their interactions that we published in Ref. [ 19 ]. In addition, we show that the resonances are due to weak atom-separation-dependent hyperfine interactions and determine their strengths.…”

“…Finally, Feshbach resonances among alkali-metal and closed-shell atoms open up the possibility of creating ultracold heteronuclear 2 Σ þ molecules [19,35,36,[40][41][42]. With the additional degree of freedom from the unpaired electron, such molecules extend the scientific relevance of ultracold molecules, currently limited to bialkali molecules [5,[43][44][45][46][47], with unique roles in the simulation of manybody systems, studies of quantum magnetism, fundamental symmetry tests, and ultracold chemistry [48][49][50][51].…”

“…We use the X 2 Σ þ BO potential from Ref. [19], which was obtained by fitting to six experimentally determined weakly bound states of the isotopologue 174 Yb 6 Li. The most weakly bound state of 173 Yb 6 Li in this potential has energy E −1;0 =h ¼ −1.8058ð34Þ GHz, where the number in parentheses is the one-standard deviation uncertainty.…”

“…In our research collaboration we investigate ultracold mixtures of alkali lithium and closed-shell ytterbium atoms [15][16][17][18][19] with their extreme mass ratio or imbalance of approximately 30. Quantum-degenerate mass-imbalanced mixtures [20][21][22] are of interest for several reasons.…”

Controlling the ac Stark effect of RbCs with dc electric and magnetic fields

“…Numerous bialkali molecules have been created in this way, including KRb [36], Cs 2 [37], Rb 2 [38], RbCs [39,40], NaK [41][42][43], NaRb [44], and NaLi [45]. Significant progress is also being made toward producing molecules from mixtures of open-shell and closed-shell atoms [46][47][48][49][50][51]. The second method employs direct laser cooling of molecules.…”