Optimal cloning of coherent states with a linear amplifier and beam splitters.
A transformation achieving the optimal symmetric N-->M cloning of coherent states is presented. Its implementation requires only a phase-insensitive linear amplifier and a network of beam splitters. An experimental demonstration of this continuous-variable cloner should therefore be in the scope of current technology. The link between optimal quantum cloning and optimal amplification of quantum states is also pointed out.
Braunstein
S L
SL
Informatics, Bangor University, Bangor LL57 1UT, United Kingdom.
Cerf
N J
NJ
Iblisdir
S
S
van Loock
P
P
Massar
S
S