Investigation of Spontaneous Raman Scattering in Combined Classical and Quantum Communication Networks

Including Quantum Key Distribution service into classical high-speed optical data transmission networks applying a dense wavelength division multiplexing technique via one joint fibre is a cost-effective solution to improve the network’s security. Several noise sources degrade the quality of the quantum channel in this multichannel system. Optical filtering cannot eliminate the optical nonlinear effects, like Spontaneous Raman Scattering caused by the classical optical channels. The paper thoroughly investigates this nonlinear optical effect with different combined classical and quantum system topologies. The applied model uses experimental values of Spontaneous Raman Scattering.