  We show that the five possible ordered states in a quantum spin-1/2 system
with long-range exchange interactions: Neel, ladder, Peierls, coincidence, and
domain states, can be realized in a binary Rydberg-dressed BEC system in the
supersolid phase. In such a system, blockade phenomenon is shown to also occur
for pairs of different excited-state atoms, which results in similar intra- and
inter-species long-range interactions between ground-state atoms. It suggests
that a pseudo spin-1/2 system can be possibly formed in the ground state of
ultracold rudibium.
