Trionic phase of ultracold fermions in an optical lattice: A variational study

Akos Rapp; Walter Hofstetter; Gergely Zarand

doi:10.1103/physrevb.77.144520

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arXiv · 0707.2378

Trionic phase of ultracold fermions in an optical lattice: A variational study

Akos Rapp·Walter Hofstetter·Gergely Zarand

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Abstract

To investigate ultracold fermionic atoms of three internal states (colors) in an optical lattice, subject to strong attractive interaction, we study the attractive three-color Hubbard model in infinite dimensions by using a variational approach. We find a quantum phase transition between a weak-coupling superconducting phase and a strong-coupling trionic phase where groups of three atoms are bound to a composite fermion. We show how the Gutzwiller variational theory can be reformulated in terms of an effective field theory with three-body interactions and how this effective field theory can be solved exactly in infinite dimensions by using the methods of dynamical mean field theory.

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Akos Rapp, Walter Hofstetter, Gergely Zarand. 2008-04-24. Trionic phase of ultracold fermions in an optical lattice: A variational study. https://doi.org/10.1103/physrevb.77.144520

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