Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Physical Review Research

Observation of magnetic Feshbach resonances between Cs and Yb173

Tobias Franzen, Alexander Guttridge, Kali Wilson, Jack Segal, Matthew D. Frye, Jeremy M. Hutson, Simon L. Cornish

Published Oct 31, 2022• 13 citations
Publisher

Abstract

We report the observation of magnetic Feshbach resonances between $^{173}\mathrm{Yb}$ and $^{133}\mathrm{Cs}$. In a mixture of Cs atoms prepared in the $(f=3,{m}_{f}=3)$ state and unpolarized fermionic $^{173}\mathrm{Yb}$, we observe resonant atom loss due to two sets of magnetic Feshbach resonances around 622 and 702 G. Resonances for individual Yb nuclear spin components ${m}_{i,\mathrm{Yb}}$ are split by its interaction with the Cs electronic spin, which also provides the main coupling mechanism for the observed resonances. The observed splittings and relative resonance strengths are in good agreement with theoretical predictions from coupled-channel calculations.

DOI
10.1103/physrevresearch.4.043072

Related papers

Observation of magnetic Feshbach resonances between Cs and ${}^{173}$Yb

Tobias Franzen, Alexander Guttridge, Kali Wilson +4 more

We report the first observation of magnetic Feshbach resonances between ${}^{173}$Yb and $^{133}$Cs. In a mixture of Cs atoms prepared in the $(f=3, m_f=3)$ state and unpolarized fermionic ${}^{173}$Yb we observe resonant atom loss due to two sets of magnetic Feshbach resonances around 622~G and 702~G. Resonances for individual Yb nuclear spin components $m_{i,\mathrm{Yb}}$ are split by its interaction with the Cs electronic spin, which also provides the main coupling mechanism for the observed resonances. The observed splittings and relative resonance strengths are in good agreement with theoretical predictions from coupled-channel calculations.

arXiv:2208.06291•Aug 12, 2022•0 citations

Magnetic Feshbach resonances in ultracold collisions between Cs and Yb atoms

Bing Yang, Matthew D. Frye, Alexander Guttridge +4 more

We investigate magnetically tunable Feshbach resonances in ultracold collisions between ground-state Yb and Cs atoms, using coupled-channel calculations based on an interaction potential recently determined from photoassociation spectroscopy. We predict resonance positions and widths for all stable isotopes of Yb, together with resonance decay parameters where appropriate. The resonance patterns are richer and more complicated for fermionic Yb than for spin-zero isotopes, because there are additional level splittings and couplings due to scalar and tensorial Yb hyperfine interactions. We examine collisions involving Cs atoms in a variety of hyperfine states and identify resonances that appear most promising for experimental observation and for magnetoassociation to form ultracold CsYb molecules.

arXiv:1905.11977•Physical Review A•Aug 15, 2019•18 citations

Spin-rotation coupling in p-wave Feshbach resonances

Bing Zhu, Häfner, Stephan, Binh Tran +4 more

We report evidence for spin-rotation coupling in $p$-wave Feshbach resonances in an ultracold mixture of fermionic $^6$Li and bosonic $^{133}$Cs lifting the commonly observed degeneracy of states with equal absolute value of orbital-angular-momentum projection on the external magnetic field. By employing magnetic field dependent atom-loss spectroscopy we find triplet structures in $p$-wave resonances. Comparison with coupled-channel calculations, including contributions from both spin-spin and spin-rotation interactions, yields a spin-rotation coupling parameter $|γ|=0.566(50)\times10^{-3}$. Our findings highlight the potential of Feshbach resonances in revealing subtle molecular couplings and providing precise information on electronic and nuclear wavefunctions, especially at short internuclear distance. The existence of a non-negligible spin-rotation splitting may have consequences for future classifications of $p$-wave superfluid phases in spin-polarized fermions.

arXiv:1910.12011•Oct 26, 2019•2 citations

High partial-wave Feshbach resonances in an ultracold $^6$Li-$^{133}$Cs mixture

Bing Zhu, Häfner, Stephan, Binh Tran +4 more

We measure higher partial wave Feshbach resonances in an ultracold mixture of fermionic $^6$Li and bosonic $^{133}$Cs by magnetic field dependent atom-loss spectroscopy. For the $p$-wave Feshbach resonances we observe triplet structures corresponding to different projections of the pair rotation angular momentum onto the external magnetic field axis. We attribute the splittings to the spin-spin and spin-rotation couplings by modelling the observation using a full coupled-channel calculation. Comparison with an oversimplified model, estimating the spin-rotation coupling by describing the weakly bound close-channel molecular state with the perturbative multipole expansion, reveals the significant contribution of the molecular wavefunction at short internuclear distances. Our findings highlight the potential of Feshbach resonances in providing precise information on short- and intermediate-range molecular couplings and wavefunctions. The observed $d$-wave Feshbach resonances allow us to refine the LiCs singlet and triplet ground-state molecular potential curves at large internuclear separations.

arXiv:1912.01264•Dec 3, 2019•2 citations

Feshbach Resonances in p -Wave Three-Body Recombination within Fermi-Fermi Mixtures of Open-Shell Li6 and Closed-Shell Yb173 Atoms

Alaina Green, Hui Li, Jun Hui See Toh +6 more

We report on the observation of magnetic Feshbach resonances in a Fermi-Fermi mixture of ultracold atoms with extreme mass imbalance and on their unique p-wave dominated three-body recombination processes.Our system consists of open-shell alkali-metal 6 Li and closed-shell 173 Yb atoms, both spin polarized and held at various temperatures between 1 and 20 μK.We confirm that Feshbach resonances in this system are solely the result of a weak separation-dependent hyperfine coupling between the electronic spin of 6 Li and the nuclear spin of 173 Yb.Our analysis also shows that three-body recombination rates are controlled by the identical fermion nature of the mixture, even in the presence of s-wave collisions between the two species and with recombination rate coefficients outside the Wigner threshold regime at our lowest temperature.Specifically, a comparison of experimental and theoretical line shapes of the recombination process indicates that the characteristic asymmetric line shape as a function of applied magnetic field and a maximum recombination rate coefficient that is independent of temperature can only be explained by triatomic collisions with nonzero, p-wave total orbital angular momentum.The resonances can be used to form ultracold doublet ground-state molecules and to simulate quantum superfluidity in mass-imbalanced mixtures.

arXiv:1912.04874•Physical Review X•Aug 14, 2020•55 citations

Magnetic Feshbach resonances in $^{7}\text{Li}-^{133}\text{Cs}$ mixtures

Pascal Naidon

Motivated by the prospect of observing Efimov and Bose polaron physics in ultracold mixtures of bosonic atoms with large mass imbalance, this work investigates the magnetic Feshbach resonances between $^{7}\text{Li}$ and $^{133}\text{Cs}$. The resonances are predicted at the 1 gauss level using the model of Pires et al. [Phys. Rev. A, 90, 012710] obtained from experimental observations of resonances between $^{6}\text{Li}$ and $^{133}\text{Cs}$. It is found that a few resonances in a practical range of magnetic field intensity could be used to tune the scattering length between $^{7}\text{Li}$ and $^{133}\text{Cs}$ atoms. Opportunities for observing Efimov and Bose polaron physics are discussed.

arXiv:2001.05329•Jan 15, 2020•1 citation
We report the observation of magnetic Feshbach resonances between 173Yb^{173}\mathrm{Yb}173Yb and 133Cs^{133}\mathrm{Cs}133Cs. In a mixture of Cs atoms prepared in the (f=3,mf=3)(f=3,{m}_{f}=3)(f=3,mf​=3) state and unpolarized fermionic 173Yb^{173}\mathrm{Yb}173Yb, we observe resonant atom loss due to two sets of magnetic Feshbach resonances around 622 and 702 G. Resonances for individual Yb nuclear spin components mi,Yb{m}_{i,\mathrm{Yb}}mi,Yb​ are split by its interaction with the Cs electronic spin, which also provides the main coupling mechanism for the observed resonances. The observed splittings and relative resonance strengths are in good agreement with theoretical predictions from coupled-channel calculations.
Observation of magnetic Feshbach resonances between Cs and 173{}^{173}173Yb
We report the first observation of magnetic Feshbach resonances between 173{}^{173}173Yb and 133^{133}133Cs. In a mixture of Cs atoms prepared in the (f=3,mf=3)(f=3, m_f=3)(f=3,mf​=3) state and unpolarized fermionic 173{}^{173}173Yb we observe resonant atom loss due to two sets of magnetic Feshbach resonances around 622~G and 702~G. Resonances for individual Yb nuclear spin components mi,Ybm_{i,\mathrm{Yb}}mi,Yb​ are split by its interaction with the Cs electronic spin, which also provides the main coupling mechanism for the observed resonances. The observed splittings and relative resonance strengths are in good agreement with theoretical predictions from coupled-channel calculations.
We investigate magnetically tunable Feshbach resonances in ultracold collisions between ground-state Yb and Cs atoms, using coupled-channel calculations based on an interaction potential recently determined from photoassociation spectroscopy. We predict resonance positions and widths for all stable isotopes of Yb, together with resonance decay parameters where appropriate. The resonance patterns are richer and more complicated for fermionic Yb than for spin-zero isotopes, because there are additional level splittings and couplings due to scalar and tensorial Yb hyperfine interactions. We examine collisions involving Cs atoms in a variety of hyperfine states and identify resonances that appear most promising for experimental observation and for magnetoassociation to form ultracold CsYb molecules.
We report evidence for spin-rotation coupling in ppp-wave Feshbach resonances in an ultracold mixture of fermionic 6^66Li and bosonic 133^{133}133Cs lifting the commonly observed degeneracy of states with equal absolute value of orbital-angular-momentum projection on the external magnetic field. By employing magnetic field dependent atom-loss spectroscopy we find triplet structures in ppp-wave resonances. Comparison with coupled-channel calculations, including contributions from both spin-spin and spin-rotation interactions, yields a spin-rotation coupling parameter ∣γ∣=0.566(50)×10−3|γ|=0.566(50)\times10^{-3}∣γ∣=0.566(50)×10−3. Our findings highlight the potential of Feshbach resonances in revealing subtle molecular couplings and providing precise information on electronic and nuclear wavefunctions, especially at short internuclear distance. The existence of a non-negligible spin-rotation splitting may have consequences for future classifications of ppp-wave superfluid phases in spin-polarized fermions.
High partial-wave Feshbach resonances in an ultracold 6^66Li-133^{133}133Cs mixture
We measure higher partial wave Feshbach resonances in an ultracold mixture of fermionic 6^66Li and bosonic 133^{133}133Cs by magnetic field dependent atom-loss spectroscopy. For the ppp-wave Feshbach resonances we observe triplet structures corresponding to different projections of the pair rotation angular momentum onto the external magnetic field axis. We attribute the splittings to the spin-spin and spin-rotation couplings by modelling the observation using a full coupled-channel calculation. Comparison with an oversimplified model, estimating the spin-rotation coupling by describing the weakly bound close-channel molecular state with the perturbative multipole expansion, reveals the significant contribution of the molecular wavefunction at short internuclear distances. Our findings highlight the potential of Feshbach resonances in providing precise information on short- and intermediate-range molecular couplings and wavefunctions. The observed ddd-wave Feshbach resonances allow us to refine the LiCs singlet and triplet ground-state molecular potential curves at large internuclear separations.
We report on the observation of magnetic Feshbach resonances in a Fermi-Fermi mixture of ultracold atoms with extreme mass imbalance and on their unique p-wave dominated three-body recombination processes.Our system consists of open-shell alkali-metal 6 Li and closed-shell 173 Yb atoms, both spin polarized and held at various temperatures between 1 and 20 μK.We confirm that Feshbach resonances in this system are solely the result of a weak separation-dependent hyperfine coupling between the electronic spin of 6 Li and the nuclear spin of 173 Yb.Our analysis also shows that three-body recombination rates are controlled by the identical fermion nature of the mixture, even in the presence of s-wave collisions between the two species and with recombination rate coefficients outside the Wigner threshold regime at our lowest temperature.Specifically, a comparison of experimental and theoretical line shapes of the recombination process indicates that the characteristic asymmetric line shape as a function of applied magnetic field and a maximum recombination rate coefficient that is independent of temperature can only be explained by triatomic collisions with nonzero, p-wave total orbital angular momentum.The resonances can be used to form ultracold doublet ground-state molecules and to simulate quantum superfluidity in mass-imbalanced mixtures.
Magnetic Feshbach resonances in 7Li−133Cs^{7}\text{Li}-^{133}\text{Cs}7Li−133Cs mixtures
Motivated by the prospect of observing Efimov and Bose polaron physics in ultracold mixtures of bosonic atoms with large mass imbalance, this work investigates the magnetic Feshbach resonances between 7Li^{7}\text{Li}7Li and 133Cs^{133}\text{Cs}133Cs. The resonances are predicted at the 1 gauss level using the model of Pires et al. [Phys. Rev. A, 90, 012710] obtained from experimental observations of resonances between 6Li^{6}\text{Li}6Li and 133Cs^{133}\text{Cs}133Cs. It is found that a few resonances in a practical range of magnetic field intensity could be used to tune the scattering length between 7Li^{7}\text{Li}7Li and 133Cs^{133}\text{Cs}133Cs atoms. Opportunities for observing Efimov and Bose polaron physics are discussed.