Abstract

In 1966, Nagaoka predicted that interaction-induced ferromagnetism occurs  in lattices with specific geometry when there is  one fewer  electron than in the half-filled system (one hole).  In this talk   I will  describe acontrollable method for observing  Nagaoka Ferromagnetism (NF) in cold atoms by loading them in optical superlattices. First  I will  discuss how to probe  NF in  an array of isolated plaquettes  (four lattice sites arranged in a square) .  Next  I will  discuss the more generic case of an array of  weakly coupled plaquettes and  suggest a method  for creating and detecting long range ferromagnetic correlations.