  We investigate the proximity effect in a heterostructure of the topological
insulator (TI) \BiSe\ deposited on the HTSC material BSCCO. The latter is
described by the one-band Hubbard model and is treated with cluster dynamical
mean field theory (CDMFT), the TI layers being included via the CDMFT
self-consistency loop. The penetration of superconductivity into the TI depends
on the position of the Fermi level with respect to the TI gap. We illustrate
the back action of the TI layer on the HTSC layer, in particular the gradual
disappearance of Mott physics with increasing tunneling amplitude.
