Rashba spin-orbit coupling for neutral atoms

We theoretically describe a new class of atom-laser coupling schemes which lead to effective spin-orbit coupled Hamiltonians for ultra-cold neutral atoms. By properly setting the optical phases, a pair of degenerate spin states emerge as the lowest energy states in the spectrum, and are thus immune to collisionally induced decay. These schemes use $N$ cyclically coupled ground or metastable internal states but we will specialize to the four-level case for this talk. Time permitting, we will describe a possible implementation of this scheme for $^{87}$Rb that adds a controllable Dresselhaus component to the effective Hamiltonian in a natural way.