A two-parametric deformation of U[sl(2)], its representations and complex "spin"

A two-parametric deformation of U[sl(2)] and its representations are considered. This newly introduced two-parametric quantum group denoted as $U_{pq}[sl(2)]$ admits a class of infinite-dimensional representations which have no classical (non-deformed) and one-parametric deformation analogues, even at generic deformation parameters. Interestingly that finite-dimensional representations of $U_{pq}[sl(2)]$ allow arbitrary complex “spins” (i.e., not necessary they to be integral or half-integral numbers), unlike those in the classical and one-parametric deformation cases.