Supersymmetric Model of Spin-1/2 Fermions on a Chain
  In recent work, N=2 supersymmetry has been proposed as a tool for the analysis of itinerant, correlated fermions on a lattice. In this paper we extend these considerations to the case of lattice fermions with spin 1/2 . We introduce a model for correlated spin-1/2 fermions with a manifest N=4 supersymmetry, and analyze its properties. The supersymmetric ground states that we find represent holes in an anti-ferromagnetic background. 
Raoul Santachiara and Kareljan Schoutens