Continuous-Variable Quantum Cloning of Coherent states with Phase-Conjugate Input Modes Using Linear Optics
نویسندگان
چکیده
We propose a scheme for continuous-variable quantum cloning of coherent states with phaseconjugate input modes using linear optics. The quantum cloning machine yields M identical optimal clones from N replicas of a coherent state and N its replicas of phase conjugate. This scheme can be straightforwardly implemented with the setup accessible at present since its optical implementation only employs simple linear optical elements and homodyne detection. Compared with the original scheme for continuous variables quantum cloning with phase-conjugate input modes proposed by Cerf and Iblisdir [Phys. Rev. Lett. 87, 247903 (2001)], which utilized a nondegenerate optical parametric amplifier, our scheme loses the output of phase-conjugate clones and is regarded as irreversible quantum cloning.
منابع مشابه
Experimental Demonstration of Continuous Variable Cloning with Phase-Conjugate Inputs
We report the experimental demonstration of continuous variable cloning of phase conjugate coherent states as proposed by Cerf and Iblisdir (Phys. Rev. Lett. 87, 247903 (2001)). In contrast to the proposal of Cerf and Iblisdir, the cloning transformation is accomplished using only linear optical components, homodyne detection and feedforward. Three clones are succesfully produced with fidelitie...
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