Representations of (1,0) and (2,0) superconformal algebras in six dimensions: Massless and short superfields

We construct unitary representations of (1,0) and (2,0) superconformal algebras in six dimensions by using superfields defined on harmonic superspaces with coset manifolds USp(2n)/[U(1)](n), n=1,2. In the spirit of the AdS(7)/CFT6 correspondence, massless conformal fields correspond to 'supersingletons' in AdS(7). By tensoring them we produce all short representations corresponding to 1/2 and 1/4 BPS anti-de Sitter bulk states of which 'massless bulk' representations are particular cases.