Chiral superfields in IIB supergravity

The field strength superfield of IIB supergravity on AdS5×S5 is expanded in harmonics on S5 with coefficients which are D=5, N=8 chiral superfields. On the boundary of AdS5 these superfields map to D=4, N=4 chiral superfields and both sets of superfields obey additional fourth-order constraints. The constraints on the D=4, N=4 chiral fields are solved using harmonic superspace in terms of prepotential superfields which couple in a natural way to composite operator multiplets of the boundary N=4, D=4 superconformal field theory.