  Massive arbitrary spin supermultiplets and massless (scalar and spin
one-half) supermultiplets of the N=2 Poincare superalgebra in three-dimensional
flat space are considered. Both the integer spin and half-integer spin
supermultiplets are studied. For such massive and massless supermultiplets, a
formulation in terms of light-cone gauge unconstrained superfields defined in a
momentum superspace is developed. For the supermultiplets under consideration a
superspace first derivative representation for all cubic interaction vertices
is obtained. A superspace representation for dynamical generators of the N=2
Poincare superalgebra is also found.
