The energy and structure of a dilute hard-disks Bose gas are studied in the framework of a variational many-body approach based on a Jastrow correlated ground-state wave function. The asymptotic behaviors of the radial distribution function and the one-body density matrix are analyzed after solving the Euler equation obtained by a free minimization of the hypernetted chain energy functional. Our results show important deviations from those of the available low density expansions, already at gas parameter values $x\ensuremath{\sim}0.001$. The condensate fraction in 2D is also computed and found generally lower than the 3D one at the same $x$ .The energy and structure of a dilute hard-disks Bose gas are studied in the framework of a variational many-body approach based on a Jastrow correlated ground-state wave function. The asymptotic behaviors of the radial distribution function and the one-body density matrix are analyzed after solving the Euler equation obtained by a free minimization of the hypernetted chain energy functional. Our results show important deviations from those of the available low density expansions, already at gas parameter values $x\ensuremath{\sim}0.001$. The condensate fraction in 2D is also computed and found generally lower than the 3D one at the same $x$.

arXiv:cond-mat/0410690Physical Review AMar 10, 200511 citations

A strongly interacting two-dimensional Fermi gas

Bernd Fröhlich

Oct 11, 20113 citations

Ferromagnetic transition of a two-component Fermi gas of hard spheres

F. Arias de Saavedra, Ferran Mazzanti, Jordi Boronat +1 more

We use microscopic many-body theory to analyze the problem of itinerant ferromagnetism in a repulsive atomic Fermi gas of hard spheres. Using simple arguments we show that the available theoretical predictions for the onset of the ferromagnetic transition predict a transition point at a density (${k}_{F}a\ensuremath{\sim}1$) that is too large to be compatible with the universal low-density expansion of the energy. We present variational calculations for the hard-sphere Fermi gas, in the framework of Fermi hypernetted chain theory, that shift the transition to higher densities (${k}_{F}a\ensuremath{\sim}1.8$). Backflow correlations, which are mainly active in the unpolarized system, are essential for this shift.We use microscopic many-body theory to analyze the problem of itinerant ferromagnetism in a repulsive atomic Fermi gas of hard spheres. Using simple arguments we show that the available theoretical predictions for the onset of the ferromagnetic transition predict a transition point at a density (${k}_{F}a\ensuremath{\sim}1$) that is too large to be compatible with the universal low-density expansion of the energy. We present variational calculations for the hard-sphere Fermi gas, in the framework of Fermi hypernetted chain theory, that shift the transition to higher densities (${k}_{F}a\ensuremath{\sim}1.8$). Backflow correlations, which are mainly active in the unpolarized system, are essential for this shift.

arXiv:1203.2521Physical Review AMar 12, 201227 citations

Two-dimensional Fermi gases

Michael Köhl

Bulletin of the American Physical SocietyJun 6, 20120 citations

A strongly interacting two-dimensional Fermi gas

Selim Jochim

Bulletin of the American Physical SocietyMar 16, 20161 citation

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