  Entangled continuous variable (CV) Gaussian states with different wavelengths
plays a central role in recent CV-based approaches to quantum network, quantum
information processing and quantum metrology. Typically, experiments
demonstrating CV entanglement exploit the optical parametric frequency down
conversion. Due to the probabilistic nature of photon pair generation, the
entanglement involving the post-selection of photonic qubits is limited to at
most three colors. Here We theoretically present a scheme for the deterministic
generation of entanglement among bright multicolor CV Gaussian states from an
optomechanical system using existing experimental technologies. In our scheme
an optical frequency comb is input into an optomechanical resonator and then
the amplified optomechanical coupling makes multipartite entanglement among
them. Our scheme overcomes the limitation of usable frequency of entangled CVs
in frequency conversion process. It can be extended to generate multipartite
entanglement between orthogonal modes with a single frequency or between
microwave and optical CVs, or even among a microwave frequency comb. This
optomechanical device can be integrated on a chip.
