arXiv:2111.08130 · Physical Review A

Feshbach resonances of large-mass-imbalance Er-Li mixtures

F. Schäfer, N. Mizukami, Yoshiro Takahashi

Published Jan 24, 2022• 22 citations

Abstract

We report on the experimental observation of Feshbach resonances in large-mass-imbalance mixtures of erbium (Er) and lithium (Li). All combinations of $^{168}\mathrm{Er}, ^{166}\mathrm{Er}$, and $^{7}\mathrm{Li}, ^{6}\mathrm{Li}$ are cooled to temperatures of a few microkelvin, partially by means of sympathetic cooling together with ytterbium (Yb) as a third mixture component. The Er-Li inelastic interspecies collisional properties are studied for magnetic fields up to $680\phantom{\rule{0.28em}{0ex}}\mathrm{G}$. In all cases, resonant interspecies loss features, indicative of Feshbach resonances, have been observed. While most resonances have sub-Gauss widths, a few of them are broad and feature widths of several Gauss. Those broad resonances are a key to the realization of ultracold Er-Li quantum gas mixtures with tunable interactions.

DOI: 10.1103/physreva.105.012816

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Observation of Feshbach Resonances in an167Er–6Li Fermi–Fermi Mixture

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arXiv:2302.14253Journal of the Physical Society of JapanApr 19, 202315 citations

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

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Feshbach resonances in an erbium-dysprosium dipolar mixture

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Feshbach spectroscopy of ultracold mixtures of Li 6 and Dy 164 atoms

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Interspecies Feshbach Resonances in an Ultracold, Optically Trapped Bose-Fermi Mixture of Cesium and Lithium

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Feshbach resonances in an ultracold Li 7 and Rb 87 mixture

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arXiv:0808.3967Physical Review AJan 29, 200960 citations

arXiv:2111.08130 · Physical Review A

Feshbach resonances of large-mass-imbalance Er-Li mixtures

F. Schäfer, N. Mizukami, Yoshiro Takahashi

Published Jan 24, 2022• 22 citations

arXiv HTML PDF

Abstract

We report on the experimental observation of Feshbach resonances in large-mass-imbalance mixtures of erbium (Er) and lithium (Li). All combinations of

^{168}\mathrm{Er}, ^{166}\mathrm{Er}

, and

^{7}\mathrm{Li}, ^{6}\mathrm{Li}

are cooled to temperatures of a few microkelvin, partially by means of sympathetic cooling together with ytterbium (Yb) as a third mixture component. The Er-Li inelastic interspecies collisional properties are studied for magnetic fields up to

680\phantom{\rule{0.28em}{0ex}}\mathrm{G}

. In all cases, resonant interspecies loss features, indicative of Feshbach resonances, have been observed. While most resonances have sub-Gauss widths, a few of them are broad and feature widths of several Gauss. Those broad resonances are a key to the realization of ultracold Er-Li quantum gas mixtures with tunable interactions.

DOI: 10.1103/physreva.105.012816

Related papers

Observation of Feshbach Resonances in an167Er–6Li Fermi–Fermi Mixture

F. Schäfer, Yuki Haruna, Yoshiro Takahashi

We present our experimental investigation of the interspecies Feshbach spectrum in a mixture of ${}^{167}$ Er( $F = 19/2, m_F = -19/2$ )- ${}^6$ Li( $F = 1/2, m_F = 1/2$ ) atoms in the microkelvin temperature regime. These temperatures are achieved by means of sympathetic cooling with ${}^{174}$ Yb as a third species. Interspecies Feshbach resonances are then identified by investigation of the Er-Li inelastic collisional properties for magnetic fields up to 800 G. Numerous narrow resonances as well as six resonances with widths above 1 G could be identified. It is these broader resonances that hold much promise for interesting future investigations of, for exmample, novel superfluid states and Efimov states in large mass-imbalanced, all-fermionic two-component systems.We present our experimental investigation of the interspecies Feshbach spectrum in a mixture of ${}^{167}$Er($F = 19/2, m_F = -19/2$)-${}^6$Li($F = 1/2, m_F = 1/2$) atoms in the microkelvin temperature regime. These temperatures are achieved by means of sympathetic cooling with ${}^{174}$Yb as a third species. Interspecies Feshbach resonances are then identified by investigation of the Er-Li inelastic collisional properties for magnetic fields up to 800 G. Numerous narrow resonances as well as six resonances with widths above 1 G could be identified. It is these broader resonances that hold much promise for interesting future investigations of, for exmample, novel superfluid states and Efimov states in large mass-imbalanced, all-fermionic two-component systems.

arXiv:2302.14253Journal of the Physical Society of JapanApr 19, 202315 citations

Magnetic Feshbach resonances in $^{7}\text{Li}-^{133}\text{Cs}$ mixturesMagnetic 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.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:2001.05329Jan 15, 20201 citation

Feshbach resonances in an erbium-dysprosium dipolar mixture

Gianmaria Durastante, Claudia Politi, Maximilian Sohmen +4 more

We report on the observation of heteronuclear magnetic Feshbach resonances in several isotope mixtures of the highly magnetic elements erbium and dysprosium. Among many narrow features, we identify two resonances with a width greater than one Gauss. We characterize one of these resonances, in a mixture of $^{168}\mathrm{Er}$ and $^{164}\mathrm{Dy}$ , in terms of loss rates and elastic cross section, and observe a temperature dependence of the on-resonance loss rate suggestive of a universal scaling associated with broad resonances. Our observations hold promise for the use of such a resonance for tuning the interspecies scattering properties in a dipolar mixture. We further compare the prevalence of narrow resonances in an $^{166}\mathrm{Er}\ensuremath{-}^{164}\mathrm{Dy}$ mixture to the single-species case, and observe an increased density of resonances in the mixture.We report on the observation of heteronuclear magnetic Feshbach resonances in several isotope mixtures of the highly magnetic elements erbium and dysprosium. Among many narrow features, we identify two resonances with a width greater than one Gauss. We characterize one of these resonances, in a mixture of $^{168}\mathrm{Er}$ and $^{164}\mathrm{Dy}$, in terms of loss rates and elastic cross section, and observe a temperature dependence of the on-resonance loss rate suggestive of a universal scaling associated with broad resonances. Our observations hold promise for the use of such a resonance for tuning the interspecies scattering properties in a dipolar mixture. We further compare the prevalence of narrow resonances in an $^{166}\mathrm{Er}\ensuremath{-}^{164}\mathrm{Dy}$ mixture to the single-species case, and observe an increased density of resonances in the mixture.

arXiv:2006.06456Physical Review ASep 21, 202055 citations

Feshbach spectroscopy of ultracold mixtures of Li 6 and Dy 164 atoms

Ke Xie, Xi Li, Yu-Yang Zhou +7 more

We report on the observation of Feshbach resonances in ultracold $^{6}\mathrm{Li}\text{\ensuremath{-}}^{164}\mathrm{Dy}$ mixtures, where $^{6}\mathrm{Li}$ atoms are respectively prepared in their three lowest spin states and $^{164}\mathrm{Dy}$ atoms are prepared in their lowest-energy state. We observe 21 interspecies scattering resonances over a magnetic-field range from 0 to 702 G using atom loss spectroscopy, three of which exhibit relatively broad widths. These broad resonances provide precise control over the interspecies interaction strength, enabling the study of strongly interacting effects in $^{6}\mathrm{Li}\text{\ensuremath{-}}^{164}\mathrm{Dy}$ mixtures. Additionally, we observe a well-isolated interspecies resonance at 700.1 G, offering a unique platform to explore novel impurity physics, where heavy dipolar $^{164}\mathrm{Dy}$ atoms are immersed in a strongly interacting Fermi superfluid of $^{6}\mathrm{Li}$ atoms.We report on the observation of Feshbach resonances in ultracold $^{6}\mathrm{Li}\text{\ensuremath{-}}^{164}\mathrm{Dy}$ mixtures, where $^{6}\mathrm{Li}$ atoms are respectively prepared in their three lowest spin states and $^{164}\mathrm{Dy}$ atoms are prepared in their lowest-energy state. We observe 21 interspecies scattering resonances over a magnetic-field range from 0 to 702 G using atom loss spectroscopy, three of which exhibit relatively broad widths. These broad resonances provide precise control over the interspecies interaction strength, enabling the study of strongly interacting effects in $^{6}\mathrm{Li}\text{\ensuremath{-}}^{164}\mathrm{Dy}$ mixtures. Additionally, we observe a well-isolated interspecies resonance at 700.1 G, offering a unique platform to explore novel impurity physics, where heavy dipolar $^{164}\mathrm{Dy}$ atoms are immersed in a strongly interacting Fermi superfluid of $^{6}\mathrm{Li}$ atoms.

Physical Review AFeb 26, 20257 citations

Interspecies Feshbach Resonances in an Ultracold, Optically Trapped Bose-Fermi Mixture of Cesium and Lithium

Marc Repp

This thesis reports on the tunability of interactions in ultracold Bose-Fermi mixtures of Cesium and Lithium. The \nfirst realization of an optically trapped \n6Li -133Cs mixture enabled to perform trap loss spectroscopy measurements to identify \nmagnetic Feshbach resonances. A total of 19 interspecies Feshbach resonances, all in the magnetic field range between 650 G and 950 G, were observed for the two energetically lowest spin states of each species. Two 5 G broad and especially two 60 G broad s-wave resonances give perspectives to produce a dipolar quantum gas of LiCs ground state molecules as well as to study the Efimov effect in highly mass imbalanced systems. In addition, a unique relative tunability of intra- and interspecies \nscattering lengths was found which makes the 6Li -133Cs system also well suited for the investigation of polarons. Evaporative cooling was performed on optically trapped samples which contained only one of the species. In this way, Bose-Einstein condensates of 6Li molecules as well as 133Cs samples at a phase-space density of p = 4 · 10^2 were prepared. All experiments were performed in a new apparatus, which has been designed and set up during this thesis.This thesis reports on the tunability of interactions in ultracold Bose-Fermi mixtures of Cesium and Lithium. The \nfirst realization of an optically trapped \n6Li -133Cs mixture enabled to perform trap loss spectroscopy measurements to identify \nmagnetic Feshbach resonances. A total of 19 interspecies Feshbach resonances, all in the magnetic field range between 650 G and 950 G, were observed for the two energetically lowest spin states of each species. Two 5 G broad and especially two 60 G broad s-wave resonances give perspectives to produce a dipolar quantum gas of LiCs ground state molecules as well as to study the Efimov effect in highly mass imbalanced systems. In addition, a unique relative tunability of intra- and interspecies \nscattering lengths was found which makes the 6Li -133Cs system also well suited for the investigation of polarons. Evaporative cooling was performed on optically trapped samples which contained only one of the species. In this way, Bose-Einstein condensates of 6Li molecules as well as 133Cs samples at a phase-space density of p = 4 · 10^2 were prepared. All experiments were performed in a new apparatus, which has been designed and set up during this thesis.

Jan 1, 20135 citations

Feshbach resonances in an ultracold Li 7 and Rb 87 mixture

C. Marzok, Benjamin Deh, Claus Zimmermann +4 more

We report on the observation of five Feshbach resonances in collisions between ultracold $^{7}\mathrm{Li}$ and $^{87}\mathrm{Rb}$ atoms in the absolute ground-state mixture where both species are in their $\ensuremath{\mid}f,{m}_{f}⟩=\ensuremath{\mid}1,1⟩$ hyperfine states. The resonances appear as trap losses for the $^{7}\mathrm{Li}$ cloud induced by inelastic heteronuclear three-body collisions. The magnetic field values where they occur are important quantities for an accurate determination of the interspecies interaction potentials. Results of coupled channels calculations based on the observed resonances are presented and refined potential parameters are given. A very broad Feshbach resonance centered around $649\phantom{\rule{0.3em}{0ex}}\mathrm{G}$ should allow for fine-tuning of the interaction strength in future experiments.We report on the observation of five Feshbach resonances in collisions between ultracold $^{7}\mathrm{Li}$ and $^{87}\mathrm{Rb}$ atoms in the absolute ground-state mixture where both species are in their $\ensuremath{\mid}f,{m}_{f}⟩=\ensuremath{\mid}1,1⟩$ hyperfine states. The resonances appear as trap losses for the $^{7}\mathrm{Li}$ cloud induced by inelastic heteronuclear three-body collisions. The magnetic field values where they occur are important quantities for an accurate determination of the interspecies interaction potentials. Results of coupled channels calculations based on the observed resonances are presented and refined potential parameters are given. A very broad Feshbach resonance centered around $649\phantom{\rule{0.3em}{0ex}}\mathrm{G}$ should allow for fine-tuning of the interaction strength in future experiments.

arXiv:0808.3967Physical Review AJan 29, 200960 citations

We report on the experimental observation of Feshbach resonances in large-mass-imbalance mixtures of erbium (Er) and lithium (Li). All combinations of

^{168}\mathrm{Er}, ^{166}\mathrm{Er}

, and

^{7}\mathrm{Li}, ^{6}\mathrm{Li}

680\phantom{\rule{0.28em}{0ex}}\mathrm{G}

We present our experimental investigation of the interspecies Feshbach spectrum in a mixture of

{}^{167}

Er(

F = 19/2, m_F = -19/2

{}^6

Li(

F = 1/2, m_F = 1/2

) atoms in the microkelvin temperature regime. These temperatures are achieved by means of sympathetic cooling with

{}^{174}

Yb as a third species. Interspecies Feshbach resonances are then identified by investigation of the Er-Li inelastic collisional properties for magnetic fields up to 800 G. Numerous narrow resonances as well as six resonances with widths above 1 G could be identified. It is these broader resonances that hold much promise for interesting future investigations of, for exmample, novel superfluid states and Efimov states in large mass-imbalanced, all-fermionic two-component systems.

Magnetic Feshbach resonances in

^{7}\text{Li}-^{133}\text{Cs}

mixtures

^{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.

^{168}\mathrm{Er}

and

^{164}\mathrm{Dy}

, in terms of loss rates and elastic cross section, and observe a temperature dependence of the on-resonance loss rate suggestive of a universal scaling associated with broad resonances. Our observations hold promise for the use of such a resonance for tuning the interspecies scattering properties in a dipolar mixture. We further compare the prevalence of narrow resonances in an $^{166}\mathrm{Er}\ensuremath{-}^{164}\mathrm{Dy}$ mixture to the single-species case, and observe an increased density of resonances in the mixture.

We report on the observation of Feshbach resonances in ultracold $^{6}\mathrm{Li}\text{\ensuremath{-}}^{164}\mathrm{Dy}$ mixtures, where

^{6}\mathrm{Li}

atoms are respectively prepared in their three lowest spin states and

^{164}\mathrm{Dy}

atoms are prepared in their lowest-energy state. We observe 21 interspecies scattering resonances over a magnetic-field range from 0 to 702 G using atom loss spectroscopy, three of which exhibit relatively broad widths. These broad resonances provide precise control over the interspecies interaction strength, enabling the study of strongly interacting effects in $^{6}\mathrm{Li}\text{\ensuremath{-}}^{164}\mathrm{Dy}$ mixtures. Additionally, we observe a well-isolated interspecies resonance at 700.1 G, offering a unique platform to explore novel impurity physics, where heavy dipolar

^{164}\mathrm{Dy}

atoms are immersed in a strongly interacting Fermi superfluid of

^{6}\mathrm{Li}

atoms.

We report on the observation of five Feshbach resonances in collisions between ultracold

^{7}\mathrm{Li}

and

^{87}\mathrm{Rb}

atoms in the absolute ground-state mixture where both species are in their $\ensuremath{\mid}f,{m}_{f}⟩=\ensuremath{\mid}1,1⟩$ hyperfine states. The resonances appear as trap losses for the

^{7}\mathrm{Li}

cloud induced by inelastic heteronuclear three-body collisions. The magnetic field values where they occur are important quantities for an accurate determination of the interspecies interaction potentials. Results of coupled channels calculations based on the observed resonances are presented and refined potential parameters are given. A very broad Feshbach resonance centered around

649\phantom{\rule{0.3em}{0ex}}\mathrm{G}

should allow for fine-tuning of the interaction strength in future experiments.