Selective cloning of Gaussian states by linear optics

Abstract

We investigate the performances of a selective cloning machine based on linear optical elements and Gaussian measurements, which allows to clone at will one of the two incoming input states. This machine is a complete generalization of a 1 to 2 cloning scheme demonstrated by U. L. Andersen et al. [Phys. Rev. Lett. vol. 94, 240503 (2005)]. The input-output fidelity is studied for generic Gaussian input state and the effect of non-unit quantum efficiency is also taken into account. We show that if the states to be cloned are squeezed states with known squeezing parameter, then the fidelity can be enhanced using a third suitable squeezed state during the final stage of the cloning process. A binary communication protocol based on the selective cloning machne is also discussed.

6 pages, 6 figures

References in corpus (16)

• Quantum information with continuous variables
• Quantum Copying: Beyond the No-Cloning Theorem
• Nonlocality of Einstein-Podolsky-Rosen State in Wigner Representation
• Universal cloning of continuous quantum variables
• Proposed Test of Quantum Nonlocality for Continuous Variables
• A theorem for the beam splitter entangler
• Fidelity for displaced squeezed states and the oscillator semigroup
• Optimal cloning of coherent states with a linear amplifier and beam splitters
• Unconditional quantum cloning of coherent states with linear optics
• Optical implementation of continuous-variable quantum cloning machines
• Optimal N-to-M Cloning of Quantum Coherent States
• Entanglement and visibility at the output of a Mach-Zehnder interferometer
• Cloning of Gaussian states by linear optics
• Distinguishing two single-mode Gaussian states by homodyne detection: An information-theoretic approach
• Improving information/disturbance and estimation/distortion trade-offs with non universal protocols
• Optimal cloning of coherent states by linear optics