Chapter 14: Quantum Information Theory and Photonic Communications

The fundamental physical limits of optical communications are discussed in the light of the recent developments in quantum information theory. The limits on channel capacities and bit error rates are described. Classical information theory is reviewed, and its relationship with the quantum information theory is examined. Recent developments in quantum information theory have opened new possibilities for transmitting classical and quantum information over optical channels. The current status of the field and the open questions are discussed.