Exotic quantum dark states

We extend studies of velocity selective coherent population trapping to ato ms having a J = 1 --> J = 0 transition. When placed in a two-dimensional la ser field these atoms are optically pumped into different velocity selectiv e nonabsorbing states. Each of these distinct energy eigenstates exhibits a unique entanglement between its internal and external degrees of freedom. We use a graphical method that makes easier the description of these states . We confirm our predictions experimentally.