Equivalence between squeezed-state and twin-beam communication channels

Modern Physics Letters B

Volumn 11, Issue 29, 1997, Pages 1263-1275

  D'Ariano, G M ^a   Sacchi, M F ^a  

^a UNIVERSITY OF PAVIA   (Italy)

Author keywords

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Indexed keywords

EID: 0000497806     PISSN: 02179849     EISSN: None     Source Type: Journal    
DOI: 10.1142/S0217984997001511     Document Type: Article

References (19)

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14. Indeed in Ref. 12 the twin-beam state is displaced asymmetrically only with respect to one mode. As a result of the symmetric displacement here we gain an additional factor 1/√2 in phase sensitivity.
15. G. M. D'Ariano and M. F. Sacchi, Repeatable two-mode phase measurement in Quantum Interferometry, Proceedings of an Adriatico Workshop, Trieste, March 1996, eds. F. De Martini, G. Denardo, Y. Shih, Verlagsleiter (Weinheim 1996), pp. 307-313.
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19. By allowing the gain parameter λ to be varied as a function of the "displacement signal" z, one might achieved a little better capacity. This is not easy to evaluate because the conditional probability would not have a Gaussian form anymore. Moreover, such a varying parameter would be very difficult to get experimentally.