  We construct highest-weight modules and a Yangian extension of the centrally
extended sl(1|1)^2 superalgebra, that is a symmetry of the worldsheet
scattering associated with the AdS3/CFT3 duality. We demonstrate that the
R-matrix intertwining atypical modules is of a trigonometric type. We also
consider a quantum deformation of this superalgebra, its modules, and obtain a
quantum affine extension of the Drinfeld-Jimbo type that describes a deformed
worldsheet scattering.
