par Gagatsos, Christos ;Karpov, Evgueni ;Cerf, Nicolas
Référence Physical Review A, 88, 012324
Publication Publié, 2012-07-20
Référence Physical Review A, 88, 012324
Publication Publié, 2012-07-20
Article révisé par les pairs
Résumé : | A non-trace-preserving map describing a probabilistic but heralded noiseless linear amplifier has recently been proposed and experimentally demonstrated. Here, we exhibit another remarkable feature of this peculiar transformation, namely its ability to serve as a universal single-mode squeezer regardless of the quadrature that is initially squeezed. Hence, it acts as a heralded phase-insensitive optical squeezer, conserving the signal-to-noise ratio just as a phase-sensitive optical amplifier but for all quadratures at the same time, whichmay offer interesting perspectives in quantum optical communications. Although this ability to squeeze all quadratures seemingly opens a way to instantaneous signaling by circumventing the quantum no-cloning theorem, we explain the subtle mechanism by which such a causality violation is forbidden, even on an heralded basis. |