Backscattering limitation for fiber-optic quantum key distribution systems
Darius Subacius, Anton Zavriyev, Alexei S. Trifonov · Applied Physics Letters · 2004
We characterized backscattering effects in optical fiber using a photon counting technique and considered its implications for quantum key distribution (QKD). We found that Rayleigh (elastic) backscattering can put strong limitations on a two-way QKD system’s performance. Raman (inelastic) scattering can restrict the ability of wavelength multiplexing of a quantum channel with strong classical data channel(s).