Lattice regularization of non-relativistic interacting fermions in (1+1) dimensions

Few-body physics plays a central role in many branches of physics, such as nuclear physics and atomic physics.

Advances in controlling ultra-cold quantum gases provide an ideal testbed for few-body physics theory. In this work, we study a three-body system composed of two different species of particles in one spatial dimension using effective field theory. Particles of the same type do not interact with each other, but particles of different types can interact via pairwise local interactions, which can depend on the relative velocity between them. We compute the binding energies of three-body bound states and analyze their dependence on the binding energy of the two-body subsystem.