  We analyze various quantum phases of ultracold bosonic atoms in a periodic
one dimensional optical superlattice. Our studies have been performed using the
finite size density matrix renormalization group (FS-DMRG) method in the
framework of the Bose-Hubbard model. Calculations have been carried out for a
wide range of densities and the energy shifts due to the superlattice
potential. At commensurate fillings, we find the Mott insulator and the
superfluid phases as well as Mott insulators induced by the superlattice. At a
particular incommensurate density, the system is found to be in the superfluid
phase coexisting with density oscillations for a certain range of parameters of
the system.
