Classical Capacity of the Lossy Bosonic Channel: The Exact Solution
Vittorio Giovannetti, Saikat Guha, Seth Lloyd, Lorenzo Maccone, J.H. Shapiro, Horace P. Yuen · Physical Review Letters · 2004
The classical capacity of the lossy bosonic channel is calculated exactly. It is shown that its Holevo information is not superadditive, and that a coherent-state encoding achieves capacity. The capacity of far-field, free-space optical communications is given as an example.