Collisional resonances of molecules can offer a deeper understanding of interaction potentials and collision complexes, and allow control of chemical reactions.Here, we experimentally map out the spectrum of Feshbach resonances in collisions between ultracold triplet rovibrational ground-state NaLi molecules and Na atoms over a range of 1400 G. Preparation of the spin-stretched state puts the system initially into the nonreactive quartet potential.A total of 25 resonances are observed, in qualitative agreement with quantum-chemistry calculations using a coupled-channels approach.Although the theory cannot predict the positions of resonances, it can account for several experimental findings and provide unprecedented insight into the nature and couplings of ultracold, strongly interacting complexes.Previous work has addressed only weakly bound complexes.We show that the main coupling mechanism results from spin-rotation and spin-spin couplings in combination with the anisotropic atom-molecule interaction, and that the collisional complexes which support the resonances have a size of 30a 0 -40a 0 .This study illustrates the potential of a combined experimental and theoretical approach.Collisional resonances of molecules can offer a deeper understanding of interaction potentials and collision complexes, and allow control of chemical reactions.Here, we experimentally map out the spectrum of Feshbach resonances in collisions between ultracold triplet rovibrational ground-state NaLi molecules and Na atoms over a range of 1400 G. Preparation of the spin-stretched state puts the system initially into the nonreactive quartet potential.A total of 25 resonances are observed, in qualitative agreement with quantum-chemistry calculations using a coupled-channels approach.Although the theory cannot predict the positions of resonances, it can account for several experimental findings and provide unprecedented insight into the nature and couplings of ultracold, strongly interacting complexes.Previous work has addressed only weakly bound complexes.We show that the main coupling mechanism results from spin-rotation and spin-spin couplings in combination with the anisotropic atom-molecule interaction, and that the collisional complexes which support the resonances have a size of 30a 0 -40a 0 .This study illustrates the potential of a combined experimental and theoretical approach.

arXiv:2303.00863Physical Review XAug 14, 202320 citations

Classification of Feshbach resonances in electron-molecule scattering

David James Spence

Jan 1, 19761 citation

Feshbach resonances in Na23+K39 mixtures and refined molecular potentials for the NaK molecule

Torsten Hartmann, Torben Schulze, Kai K. Voges +5 more

We present a detailed study of interspecies Feshbach resonances of the bosonic $^{23}\mathrm{Na}+^{39}\mathrm{K}$ mixture for magnetic fields up to $750\phantom{\rule{0.16em}{0ex}}\mathrm{G}$ in various collision channels. A total of 14 Feshbach resonances are reported, as well as four zero crossings of the scattering length and three inelastic two-body loss features. We use the observed magnetic-field locations of the resonant features together with the known data on $^{23}\mathrm{Na}+^{40}\mathrm{K}$ to refine the singlet and triplet ground-state potentials of NaK and achieve a consistent description of Feshbach resonances for both the Bose-Bose mixture of $^{23}\mathrm{Na}+^{39}\mathrm{K}$ and the Bose-Fermi mixture of $^{23}\mathrm{Na}+^{40}\mathrm{K}$ . We also discuss the influence of the interplay between inelastic two-body and three-body processes on the observation of a Feshbach resonance.We present a detailed study of interspecies Feshbach resonances of the bosonic $^{23}\mathrm{Na}+^{39}\mathrm{K}$ mixture for magnetic fields up to $750\phantom{\rule{0.16em}{0ex}}\mathrm{G}$ in various collision channels. A total of 14 Feshbach resonances are reported, as well as four zero crossings of the scattering length and three inelastic two-body loss features. We use the observed magnetic-field locations of the resonant features together with the known data on $^{23}\mathrm{Na}+^{40}\mathrm{K}$ to refine the singlet and triplet ground-state potentials of NaK and achieve a consistent description of Feshbach resonances for both the Bose-Bose mixture of $^{23}\mathrm{Na}+^{39}\mathrm{K}$ and the Bose-Fermi mixture of $^{23}\mathrm{Na}+^{40}\mathrm{K}$. We also discuss the influence of the interplay between inelastic two-body and three-body processes on the observation of a Feshbach resonance.

arXiv:1810.00608Physical Review AMar 27, 201918 citations

Decay of Feshbach Resonances in Diatomic Molecules

Hélène Lefebvre-Brion, Annick Giusti-Suzor

Springer eBooksJan 1, 19830 citations

Theoretical analysis of the coupling between Feshbach states and hyperfine excited states in the creation of 23Na40K molecule*

Ya-Xiong Liu, Bo Zhao

We present an intensive study of the coupling between different Feshbach states and the hyperfine levels of the excited states in the adiabatic creation of 23Na40K ground-state molecules. We use coupled-channel method to calculate the wave function of the Feshbach molecules, and give the short-range wave function of triplet component. The energies of the hyperfine excited states and the coupling strength between the Feshbach states and the hyperfine excited states are calculated. Our results can be used to prepare a specific hyperfine level of the rovibrational ground state to study the ultracold collisions involving molecules.We present an intensive study of the coupling between different Feshbach states and the hyperfine levels of the excited states in the adiabatic creation of 23Na40K ground-state molecules. We use coupled-channel method to calculate the wave function of the Feshbach molecules, and give the short-range wave function of triplet component. The energies of the hyperfine excited states and the coupling strength between the Feshbach states and the hyperfine excited states are calculated. Our results can be used to prepare a specific hyperfine level of the rovibrational ground state to study the ultracold collisions involving molecules.

Chinese Physics BDec 18, 20199 citations

Broad Feshbach resonances in collisions of Dy atoms

Paul S. Julienne, Krzysztof Jachymski, Thomas Maier +6 more

Bulletin of the American Physical SocietyMay 24, 20160 citations

We present a detailed study of interspecies Feshbach resonances of the bosonic

^{23}\mathrm{Na}+^{39}\mathrm{K}

mixture for magnetic fields up to

750\phantom{\rule{0.16em}{0ex}}\mathrm{G}

in various collision channels. A total of 14 Feshbach resonances are reported, as well as four zero crossings of the scattering length and three inelastic two-body loss features. We use the observed magnetic-field locations of the resonant features together with the known data on

^{23}\mathrm{Na}+^{40}\mathrm{K}

to refine the singlet and triplet ground-state potentials of NaK and achieve a consistent description of Feshbach resonances for both the Bose-Bose mixture of

^{23}\mathrm{Na}+^{39}\mathrm{K}

and the Bose-Fermi mixture of

^{23}\mathrm{Na}+^{40}\mathrm{K}

. We also discuss the influence of the interplay between inelastic two-body and three-body processes on the observation of a Feshbach resonance.