Dynamic structure function of a cold Fermi gas at unitarity

Abstract

We present a theoretical study of the dynamic structure function of a resonantly interacting two-component Fermi gas at zero temperature. Our approach is based on dynamic many-body theory able to describe excitations in strongly correlated Fermi systems. The fixed-node diffusion Monte Carlo method is used to produce the ground-state correlation functions which are used as an input for the excitation theory. Our approach reproduces recent Bragg scattering data in both the density and the spin channel. In the BCS regime, the response is close to that of the ideal Fermi gas. On the BEC side, the Bose peak associated with the formation of dimers dominates the density channel of the dynamic response. When the fraction of dimers is large our theory departs from the experimental data, mainly in the spin channel.

6 pages

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Cited by in corpus (5)

• Quantum Monte Carlo estimation of complex-time correlations for the study of the ground-state dynamic structure function
• Static response, collective frequencies and ground state thermodynamical properties of spin saturated two-component cold atoms and neutron matter
• Dynamic structure factor of a strongly correlated Fermi superfluid within a density functional theory approach
• Spin-dependent Bragg spectroscopy of a spinor Bose gas
• The normal state of attractive Fermi gases from coupled-cluster theory