Magnetism and domain formation in SU(3)-symmetric multi-species Fermi mixtures

TL;DR

This paper explores the phase diagram of SU(3)-symmetric three-component ultracold fermions in optical lattices, revealing how magnetism and superfluidity interplay, and how three-body constraints influence phase stability and transitions.

Contribution

It provides a detailed analysis of the effects of three-body constraints on magnetism and superfluidity in SU(3) fermionic mixtures using advanced theoretical methods.

Findings

Color superfluid phase is always magnetized away from particle-hole symmetry.

Three-body constraints suppress trionic phases and stabilize color superfluidity.

Temperature induces a transition from magnetized superfluid to a non-magnetized Fermi liquid.

Abstract

We study the phase diagram of an SU(3)-symmetric mixture of three-component ultracold fermions with attractive interactions in an optical lattice, including the additional effect on the mixture of an effective three-body constraint induced by three-body losses. We address the properties of the system in $D \geq 2$ by using dynamical mean-field theory and variational Monte Carlo techniques. The phase diagram of the model shows a strong interplay between magnetism and superfluidity. In the absence of the three-body constraint (no losses), the system undergoes a phase transition from a color superfluid phase to a trionic phase, which shows additional particle density modulations at half-filling. Away from the particle-hole symmetric point the color superfluid phase is always spontaneously magnetized, leading to the formation of different color superfluid domains in systems where the total number of particles of each species is conserved. This can be seen as the SU(3) symmetric realization of a more general tendency to phase-separation in three-component Fermi mixtures. The three-body constraint strongly disfavors the trionic phase, stabilizing a (fully magnetized) color superfluid also at strong coupling. With increasing temperature we observe a transition to a non-magnetized SU(3) Fermi liquid phase.