Comment on 'Secure Communication using mesoscopic coherent states', Barbosa et al, Phys Rev Lett 90, 227901 (2003)

Z. L. Yuan, A. J. Shields

In a recent letter, Barbosa et al [PRL 90, 227901(2003)] claim that secure communication is possible with bright coherent pulses, by using quantum noise to hide the data from an ea…