  Entangled photons are crucial for quantum technologies, but generating
arbitrary entangled photon states deterministically, efficiently, and with high
fidelity remains a challenge. Here, we demonstrate how hybridization and
dipole-dipole interactions -- potentially simultaneously available in colloidal
quantum dots and molecular aggregates -- leveraged in conjunction can couple
simple, well understood emitters into composite emitters with flexible control
over the level structure. We show that cascade decay through carefully designed
level structures can result in emission of frequency-entangled photons with
Bell states and three-photon GHZ states as example cases. These results pave
the way toward rational design of quantum optical emitters of arbitrarily
entangled photons.
