  We show how the phase profile of Bose-Einstein condensates can be engineered
through its in- teraction with localized Rydberg excitations. The interaction
is made controllable and long-range by off-resonantly coupling the condensate
to another Rydberg state with laser light. Our technique allows the mapping of
entanglement generated in systems of few strongly interacting Rydberg atoms
onto much larger atom clouds in hybrid setups. As an example we discuss the
creation of a spatial mesoscopic superposition state from a bright soliton.
Additionally, the phase imprinted onto the condensate using the Rydberg
excitations is a diagnostic tool for the latter. For example a condensate
time-of-flight image would permit reconstructing the pattern of an embedded
Rydberg crystal.
