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

Strongly Interacting Atoms and Molecules in a 3D Optical Lattice

Michael Köhl, Kenneth Günter, Thilo Stöferle, Tilman Esslinger

Published Jan 1, 2006• 2 citations
OpenAlex

Abstract

Abstract. We report on the realization of a strongly interacting quantum degenerate gas of fermionic atoms in a three-dimensional optical lattice. We prepare a bandinsulating state for a two-component Fermi gas with one atom per spin state per lattice site. Using a Feshbach resonance, we induce strong interactions between the atoms. When sweeping the magnetic field from the repulsive side towards the attractive side of the Feshbach resonance we induce a coupling between Bloch bands leading to a transfer of atoms from the lowest band into higher bands. Sweeping the magnetic field across the Feshbach resonance from the attractive towards the repulsive side leads to two-particle bound states and ultimately to the formation of molecules. From the fraction of formed molecules we determine the temperature of the atoms in the lattice.

Related papers

Strongly interacting atoms and molecules in a 3D optical lattice

Michael Köhl, Kenneth Günter, Thilo Stöferle +2 more

We report on the realization of a strongly interacting quantum degenerate gas of fermionic atoms in a three-dimensional optical lattice. We prepare a band-insulating state for a two-component Fermi gas with one atom per spin state per lattice site. Using a Feshbach resonance, we induce strong interactions between the atoms. When sweeping the magnetic field from the repulsive side towards the attractive side of the Feshbach resonance we induce a coupling between Bloch bands leading to a transfer of atoms from the lowest band into higher bands. Sweeping the magnetic field across the Feshbach resonance from the attractive towards the repulsive side leads to two-particle bound states and ultimately to the formation of molecules. From the fraction of formed molecules we determine the temperature of the atoms in the lattice.

arXiv:cond-mat/0605099•Journal of Physics B Atomic Molecular and Optical Physics•May 2, 2006•13 citations

FERMIONIC ATOMS WITH TUNABLE INTERACTIONS IN A 3D OPTICAL LATTICE

Thilo Stöferle, Henning Moritz, C. Schori +3 more

We report on the realization of a quantum degenerate atomic Fermi gas in an optical lattice. Fermi surfaces of noninteracting fermions are studied in a three-dimensional lattice. Using a Feshbach resonance, we observe a coupling of the Bloch bands in the strongly interacting regime.

arXiv:cond-mat/0601045•Laser Spectroscopy•Dec 1, 2005•1 citation

Fermionic Atoms in a Three Dimensional Optical Lattice: Observing Fermi Surfaces, Dynamics, and Interactions

Michael Köhl, Henning Moritz, Thilo Stöferle +2 more

We have studied interacting and noninteracting quantum degenerate Fermi gases in a three-dimensional optical lattice. We directly image the Fermi surface of the atoms in the lattice by turning off the optical lattice adiabatically. Because of the confining potential, gradual filling of the lattice transforms the system from a normal state into a band insulator. The dynamics of the transition from a band insulator to a normal state is studied, and the time scale is measured to be an order of magnitude larger than the tunneling time in the lattice. Using a Feshbach resonance, we increase the interaction between atoms in two different spin states and dynamically induce a coupling between the lowest energy bands. We observe a shift of this coupling with respect to the Feshbach resonance in free space which is anticipated for strongly confined atoms.

arXiv:cond-mat/0410389•Physical Review Letters•Mar 4, 2005•662 citations

Radio-Frequency Spectroscopy of a Strongly Interacting Two-Dimensional Fermi Gas

Bernd Fröhlich, Michael Feld, Enrico Vogt +3 more

We realize and study a strongly interacting two-component atomic Fermi gas confined to two dimensions in an optical lattice. Using radio-frequency spectroscopy we measure the interaction energy of the strongly interacting gas. We observe the confinement-induced Feshbach resonance on the attractive side of the 3D Feshbach resonance and find the existence of confinement-induced molecules in very good agreement with theoretical predictions.

arXiv:1012.0049•Physical Review Letters•Mar 8, 2011•231 citations

Interacting Feshbach Molecules

Niels Syassen

This thesis reports on experiments with ultracold atomic and molecular quantum gases. Magnetically tunable Feshbach resonances are used to associate diatomic molecules from atomic 87Rb in a three-dimensional optical lattice. In a first experiment, molecules are formed by a sudden jump of the magnetic field to the resonance. This induces coherent atom-molecule oscillations with large amplitude. In another experiment, a dissipative analog of the one-dimensional Tonks-Girardeau gas is realized with molecules in an optical lattice. Inelastic collisions between the molecules lead to particle loss. This interaction is so strong that the system reaches the strongly correlated regime, and the molecules, which are bosons, are forced to behave much like fermions. The strong correlations suppress the molecule loss rate by up to three orders of magnitude.

•Jan 1, 2008•1 citation

Ramping fermions in optical lattices across a Feshbach resonance

Helmut G. Katzgraber, Aniello Esposito, Matthias Troyer

We study the properties of ultracold Fermi gases in a three-dimensional optical lattice when crossing a Feshbach resonance. By using a zero-temperature formalism, we show that three-body processes are enhanced in a lattice system in comparison to the continuum case. This poses one possible explanation for the short molecule lifetimes found when decreasing the magnetic field across a Feshbach resonance. Effects of finite temperatures on the molecule formation rates are also discussed by computing the fraction of double-occupied sites. Our results show that current experiments are performed at temperatures considerably higher than expected: lower temperatures are required for fermionic systems to be used to simulate quantum Hamiltonians. In addition, by relating the double occupancy of the lattice to the temperature, we provide a means for thermometry in fermionic lattice systems, previously not accessible experimentally. The effects of ramping a filled lowest band across a Feshbach resonance when increasing the magnetic field are also discussed: fermions are lifted into higher bands due to entanglement of Bloch states, in good agreement with recent experiments.

arXiv:cond-mat/0510194•Physical Review A•Oct 2, 2006•8 citations
Abstract. We report on the realization of a strongly interacting quantum degenerate gas of fermionic atoms in a three-dimensional optical lattice. We prepare a bandinsulating state for a two-component Fermi gas with one atom per spin state per lattice site. Using a Feshbach resonance, we induce strong interactions between the atoms. When sweeping the magnetic field from the repulsive side towards the attractive side of the Feshbach resonance we induce a coupling between Bloch bands leading to a transfer of atoms from the lowest band into higher bands. Sweeping the magnetic field across the Feshbach resonance from the attractive towards the repulsive side leads to two-particle bound states and ultimately to the formation of molecules. From the fraction of formed molecules we determine the temperature of the atoms in the lattice.
We report on the realization of a strongly interacting quantum degenerate gas of fermionic atoms in a three-dimensional optical lattice. We prepare a band-insulating state for a two-component Fermi gas with one atom per spin state per lattice site. Using a Feshbach resonance, we induce strong interactions between the atoms. When sweeping the magnetic field from the repulsive side towards the attractive side of the Feshbach resonance we induce a coupling between Bloch bands leading to a transfer of atoms from the lowest band into higher bands. Sweeping the magnetic field across the Feshbach resonance from the attractive towards the repulsive side leads to two-particle bound states and ultimately to the formation of molecules. From the fraction of formed molecules we determine the temperature of the atoms in the lattice.
We have studied interacting and noninteracting quantum degenerate Fermi gases in a three-dimensional optical lattice. We directly image the Fermi surface of the atoms in the lattice by turning off the optical lattice adiabatically. Because of the confining potential, gradual filling of the lattice transforms the system from a normal state into a band insulator. The dynamics of the transition from a band insulator to a normal state is studied, and the time scale is measured to be an order of magnitude larger than the tunneling time in the lattice. Using a Feshbach resonance, we increase the interaction between atoms in two different spin states and dynamically induce a coupling between the lowest energy bands. We observe a shift of this coupling with respect to the Feshbach resonance in free space which is anticipated for strongly confined atoms.
This thesis reports on experiments with ultracold atomic and molecular quantum gases. Magnetically tunable Feshbach resonances are used to associate diatomic molecules from atomic 87Rb in a three-dimensional optical lattice. In a first experiment, molecules are formed by a sudden jump of the magnetic field to the resonance. This induces coherent atom-molecule oscillations with large amplitude. In another experiment, a dissipative analog of the one-dimensional Tonks-Girardeau gas is realized with molecules in an optical lattice. Inelastic collisions between the molecules lead to particle loss. This interaction is so strong that the system reaches the strongly correlated regime, and the molecules, which are bosons, are forced to behave much like fermions. The strong correlations suppress the molecule loss rate by up to three orders of magnitude.
We study the properties of ultracold Fermi gases in a three-dimensional optical lattice when crossing a Feshbach resonance. By using a zero-temperature formalism, we show that three-body processes are enhanced in a lattice system in comparison to the continuum case. This poses one possible explanation for the short molecule lifetimes found when decreasing the magnetic field across a Feshbach resonance. Effects of finite temperatures on the molecule formation rates are also discussed by computing the fraction of double-occupied sites. Our results show that current experiments are performed at temperatures considerably higher than expected: lower temperatures are required for fermionic systems to be used to simulate quantum Hamiltonians. In addition, by relating the double occupancy of the lattice to the temperature, we provide a means for thermometry in fermionic lattice systems, previously not accessible experimentally. The effects of ramping a filled lowest band across a Feshbach resonance when increasing the magnetic field are also discussed: fermions are lifted into higher bands due to entanglement of Bloch states, in good agreement with recent experiments.