  We propose a scheme in which broadband nanostructures allow to generate
squeezed light and entanglement of quantum emitters that are extremely far
detuned. It is shown that the reduced fluctuations of the electromagnetic field
arising from collective resonance fluorescence provide also a means to detect
the entanglement between the emitters. Due to the near-field enhancement in the
proposed hybrid systems, these nonclassical effects can be encountered outside
both the extremely close separations limiting the observation in free space and
narrow frequency bands in high-Q cavities. Our approach permits to overcome the
limitations of noninteracting single emitters and is more robust against phase
decoherence induced by the environment.
