  We propose the realization of topological quantum states with cold atoms
trapped in an optical lattice. We discuss an experimental setup that generates
a two-dimensional hexagonal lattice in the presence of a light-induced periodic
vector potential, which represents a realization of the Haldane model with cold
atoms. We determine theoretically the conditions necessary for observing the
topological states and show that two of the key conditions are: 1) the
realization of sharp boundaries and 2) the minimization of any smoothly varying
component of the confining potential. We argue that, unlike their condensed
matter counterparts, cold atom topological quantum states can be i) "seen", by
mapping out the characteristic chiral edge states, and ii) controlled, by
controlling the periodic vector potential and the properties of the confining
potential.
