Abstract : We observed the Efimov effect the existence of a series of bound three body states related to one another by a universal geometric scaling factor in a three-component Fermi gas. Our work was the first to observe, in any physical system, an excited Efimov trimer state. In related work, we created a degenerate Fermi gas with SU(3) symmetry, a first step toward the quantum simulation of phenomena in QCD such as color superconductivity. Working with two-component Fermi gases, we demonstrated that narrow Feshbach resonances could be used to explore Fermi gases with energy and momentum dependent s-wave interactions. We also observed, for the first time, an s-wave collisional frequency shift of a clock transition in a Fermi gas when a spatially inhomogeneous excitation field is used to interrogate the atoms. This work is directly relevant to state-of-the-art optical lattice clocks where spatial inhomogeneities in the clock field are nonnegligible since the field varies over the scale of an optical wavelength. Toward the study of strongly correlated Fermi gases, we have demonstrated the rapid control of interactions in a Fermi gas which will allow for diagnostics of strongly correlated Fermi gases of 6-Li and have implemented a site-resolved 2D triangular/honeycomb optical lattice which should permit the observation of anti-ferromagnetic ordering in the Hubbard model.
Abstract We investigate color superfluidity and trimer formation in resonantly interacting SU(3) Fermi gases with a finite interaction range. The finite range is crucial to avoid the Thomas collapse and treat the Efimov effect occurring in this system. Using the Skorniakov–Ter-Martirosian equation with medium effects, we show the effects of the atomic Fermi distribution on the Efimov trimer energy at finite temperature. We show the critical temperature of color superfluidity within the many-body T-matrix approximation. In this way, we can provide a first insight into the phase diagram as a function of the temperature T and the chemical potential μ. This phase diagram consists of trimer, normal, and color-superfluid phases, and is similar to that of quantum chromodynamics at finite density and temperature.
Quantum criticality of strongly attractive Fermi gas with
SU(3) symmetry in one dimension is studied via the thermodynamic Bethe ansatz (TBA) equations.The phase transitions driven by the chemical potential
μ, effective magnetic field
H1,
H2 (chemical potential biases) are analyzed at the quantum criticality. The phase diagram and critical fields are analytically determined by the thermodynamic Bethe ansatz equations in zero temperature limit. High accurate equations of state, scaling functions are also obtained analytically for the strong interacting gases. The dynamic exponent
z=2 and correlation length exponent
ν=1/2 read off the universal scaling form. It turns out that the quantum criticality of the three-component gases involves a sudden change of density of states of one cluster state, two or three cluster states. In general, this method can be adapted to deal with the quantum criticality of multi-component Fermi gases with
SU(N) symmetry.