Transmitting ultra-weak quantum states across the same glass strands carrying multi-terabit classical DWDM telecom traffic without dedicated dark fiber lease costs.
High-power classical telecom lasers (+0 dBm) leak billions of noise photons across a 200 nm spectral spread via spontaneous Raman scattering. QuantumMetroNet places quantum channels on the short-wavelength edge of the 1550 nm C-Band and uses cascading fiber Bragg gratings (FBG) to provide over 110 dB of out-of-band rejection.
Four-wave mixing (FWM) products between classical pump lasers can land directly within quantum channel passbands. The network scheduler dynamically allocates wavelength slots across asymmetric ITU grid spacings, guaranteeing that third-order intermodulation products never intersect quantum detector filters.