We study the three-point equal-time correlations of the density in a weakly interacting spin 1/2 Fermi gas and present two new results. First, we compute the three-point correlation for the total density $ρ= ρ_\uparrow + ρ_\downarrow$ exactly as a function of momentum to first order in a dimensionless interaction parameter ${\cal I}$ . This generalizes a previous result that related the three-point function to the Landau Fermi liquid parameters $F_0^s$ and $F_0^a$ and applied in a certain long-wavelength collinear limit. Second, we compute the leading order ${\cal O}({\cal I}^3)$ interaction correction to the same-spin three-point correlation function in the long-wavelength collinear limit. These results are directly relevant to current experiments on atomic Fermi gases using quantum gas microscopy.We study the three-point equal-time correlations of the density in a weakly interacting spin 1/2 Fermi gas and present two new results. First, we compute the three-point correlation for the total density $ρ= ρ_\uparrow + ρ_\downarrow$ exactly as a function of momentum to first order in a dimensionless interaction parameter ${\cal I}$. This generalizes a previous result that related the three-point function to the Landau Fermi liquid parameters $F_0^s$ and $F_0^a$ and applied in a certain long-wavelength collinear limit. Second, we compute the leading order ${\cal O}({\cal I}^3)$ interaction correction to the same-spin three-point correlation function in the long-wavelength collinear limit. These results are directly relevant to current experiments on atomic Fermi gases using quantum gas microscopy.

arXiv:2607.05747Jul 7, 20260 citations

Light interaction with resonance

Philippe Lalanne

May 18, 20160 citations

p -Wave Interactions in Low-Dimensional Fermionic Gases

Kenneth Günter, Thilo Stöferle, Henning Moritz +2 more

We study a spin-polarized degenerate Fermi gas interacting via a p-wave Feshbach resonance in an optical lattice. The strong confinement available in this system allows us to realize one- and two-dimensional gases and, therefore, to restrict the asymptotic scattering states of atomic collisions. When aligning the atomic spins along (or perpendicular to) the axis of motion in a one-dimensional gas, scattering into channels with the projection of the angular momentum of /m/ = 1 (or m = 0) can be inhibited. In two and three dimensions, we observe the doublet structure of the p-wave Feshbach resonance. For both the one-dimensional and the two-dimensional gases, we find a shift of the position of the resonance with increasing confinement due to the change in collisional energy. In a three-dimensional optical lattice, the losses on the Feshbach resonance are completely suppressed.We study a spin-polarized degenerate Fermi gas interacting via a p-wave Feshbach resonance in an optical lattice. The strong confinement available in this system allows us to realize one- and two-dimensional gases and, therefore, to restrict the asymptotic scattering states of atomic collisions. When aligning the atomic spins along (or perpendicular to) the axis of motion in a one-dimensional gas, scattering into channels with the projection of the angular momentum of /m/ = 1 (or m = 0) can be inhibited. In two and three dimensions, we observe the doublet structure of the p-wave Feshbach resonance. For both the one-dimensional and the two-dimensional gases, we find a shift of the position of the resonance with increasing confinement due to the change in collisional energy. In a three-dimensional optical lattice, the losses on the Feshbach resonance are completely suppressed.

arXiv:cond-mat/0507632Physical Review LettersNov 28, 2005215 citations

Frequency shift in three-photon resonant four-wave mixing by internal atom-field interaction

Natalia R. de Melo, S. S. Vianna

We report on experimental results of four-wave mixing processes in rubidium vapor where coherence is induced on the three-photon resonant transition from $5s$ to $6p$ states via intermediate Rydberg levels. It is shown that the use of two beams in a noncollinear configuration, i.e., $\ensuremath{\theta}\ensuremath{\ne}0$, and high atomic density unveil new features. First, the $\ensuremath{\theta}=0$ (collinear configuration) odd-photon destructive interference between the incident and generated fields is strongly inhibited for $\ensuremath{\theta}\ensuremath{\ne}0$. Second, most importantly, the observed cooperative frequency shift of the three-photon transition is strongly enhanced for small, but nonzero, values of $\ensuremath{\theta}$ due to the factor ${(1\ensuremath{-}cos\ensuremath{\theta})}^{\ensuremath{-}1}$, which is not present if the generated radiation field is not considered self-consistently in the Maxwell-Bloch equations.We report on experimental results of four-wave mixing processes in rubidium vapor where coherence is induced on the three-photon resonant transition from $5s$ to $6p$ states via intermediate Rydberg levels. It is shown that the use of two beams in a noncollinear configuration, i.e., $\ensuremath{\theta}\ensuremath{\ne}0$, and high atomic density unveil new features. First, the $\ensuremath{\theta}=0$ (collinear configuration) odd-photon destructive interference between the incident and generated fields is strongly inhibited for $\ensuremath{\theta}\ensuremath{\ne}0$. Second, most importantly, the observed cooperative frequency shift of the three-photon transition is strongly enhanced for small, but nonzero, values of $\ensuremath{\theta}$ due to the factor ${(1\ensuremath{-}cos\ensuremath{\theta})}^{\ensuremath{-}1}$, which is not present if the generated radiation field is not considered self-consistently in the Maxwell-Bloch equations.

Physical Review ANov 11, 20154 citations

ρ= ρ_\uparrow + ρ_\downarrow

exactly as a function of momentum to first order in a dimensionless interaction parameter

{\cal I}

. This generalizes a previous result that related the three-point function to the Landau Fermi liquid parameters

F_0^s

and

F_0^a

and applied in a certain long-wavelength collinear limit. Second, we compute the leading order

{\cal O}({\cal I}^3)

interaction correction to the same-spin three-point correlation function in the long-wavelength collinear limit. These results are directly relevant to current experiments on atomic Fermi gases using quantum gas microscopy.

We report on experimental results of four-wave mixing processes in rubidium vapor where coherence is induced on the three-photon resonant transition from

5s

6p

states via intermediate Rydberg levels. It is shown that the use of two beams in a noncollinear configuration, i.e., $\ensuremath{\theta}\ensuremath{\ne}0$, and high atomic density unveil new features. First, the $\ensuremath{\theta}=0$ (collinear configuration) odd-photon destructive interference between the incident and generated fields is strongly inhibited for $\ensuremath{\theta}\ensuremath{\ne}0$. Second, most importantly, the observed cooperative frequency shift of the three-photon transition is strongly enhanced for small, but nonzero, values of $\ensuremath{\theta}$ due to the factor ${(1\ensuremath{-}cos\ensuremath{\theta})}^{\ensuremath{-}1}$, which is not present if the generated radiation field is not considered self-consistently in the Maxwell-Bloch equations.