Abstract:

One growth field in cold-atom physics is the trapping of atoms in laser 
standing waves (so-called "optical lattices").  This has raised the 
exciting prospect of using these systems to simulate condensed matter's 
hard-to-solve models, with the optical lattice playing the role of the 
ionic potential and the atoms acting as the electrons.  Indeed, Immanuel 
Bloch has gone so far as to call these systems "artificial crystals of 
light".

This scheme has many attractions, notably the tunability of the model 
parameters and the complete absence of disorder (unless it's put in 
deliberately).  But there are also complications: not only is the 
simulation system much smaller than a real condensed matter one, but the 
atoms are confined differently from the electrons in a solid.

I shall show that this difference in confinement can cause qualitative 
differences between the cold-atom and solid-state cases, and discuss how 
to overcome this problem to obtain quantitative results from such 
simulation schemes.