Effect of three-body loss on itinerant ferromagnetism in an atomic Fermi gas

Understand

A recent experiment has provided the first evidence for itinerant ferromagnetism in an ultracold atomic gas of fermions with repulsive interactions.

• However, the gas in this regime is also subject to significant three-body loss.
• We adopt an extended Hertz-Millis theory to account for the effect of loss on the transition and on the ferromagnetic state.
• We find that the losses damp quantum fluctuations and thereby significantly increase the critical interaction strength needed to induce ferromagnetism.