  The control and manipulation of quantum-entangled non-local states is a
crucial step for the development of quantum information processing. A promising
route to achieve such states on a wide scale is to couple solid-state quantum
emitters through their coherent dipole-dipole interactions. Entanglement in
itself is challenging, as it requires both nanometric distances between
emitters and nearly degenerate electronic transitions. Implementing
hyperspectral imaging to identify pairs of coupled organic molecules trapped in
a low temperature matrix, we reach distinctive spectral signatures of maximal
molecular entanglement by tuning the optical resonances of the quantum emitters
by Stark effect. We also demonstrate far-field selective excitation of the
long-lived subradiant delocalized states with a laser field tailored in
amplitude and phase. Interestingly, optical nanoscopy images of the entangled
molecules unveil novel spatial signatures that result from quantum
interferences in their excitation pathways and reveal the exact locations of
each quantum emitter. Controlled molecular entanglement can serve as a
test-bench to decipher more complex physical or biological mechanisms governed
by the coherent coupling and paves the way towards the realization of new
quantum information processing platforms.
