We investigate the quantum properties of fields generated by resonantly enh
anced wave mixing based on atomic coherence in Raman systems. We show that
such a process can be used for generation of pairs of Stokes and anti-Stoke
s fields with nearly perfect quantum correlations, yielding almost complete
(i.e., 100%) squeezing without the use of a cavity. We discuss the extensi
on of the wave mixing interactions into the domain of a few interacting lig
ht quanta. [S0031-9007(99)08560-9].