Improving teleportation of continuous variables by local operations

Abstract

We study a continuous-variable (CV) teleportation protocol based on a shared entangled state produced by the quantum-nondemolition (QND) interaction of two vacuum states. The scheme utilizes the QND interaction or an unbalanced beam splitter in the Bell measurement. It is shown that in the non-unity gain regime the signal transfer coefficient can be enhanced while the conditional variance product remains preserved by applying appropriate local squeezing operation on sender's part of the shared entangled state. In the unity gain regime it is demonstrated that the fidelity of teleportation can be increased with the help of the local squeezing operations on parts of the shared entangled state that convert effectively our scheme to the standard CV teleportation scheme. Further, it is proved analytically that such a choice of the local symplectic operations minimizes the noise by which the mean number of photons in the input state is increased during the teleportation. Finally, our analysis reveals that the local symplectic operation on sender's side can be integrated into the Bell measurement if the interaction constant of the interaction in the Bell measurement can be adjusted properly.

10 pages, 1 figure, discussion of the non-unity gain teleportation is added

References in corpus (17)

• Experimental quantum teleportation
• A computable measure of entanglement
• Experimental Realization of Teleporting an Unknown Pure Quantum State via Dual Classical and Einstein-Podolski-Rosen Channels
• Experimental long-lived entanglement of two macroscopic objects
• Teleportation of Quantum States
• Extremal entanglement and mixedness in continuous variable systems
• Multipartite entanglement for continuous variables: A quantum teleportation network
• Experimental investigation of continuous variable quantum teleportation
• Quantum communication between atomic ensembles using coherent light
• Quantum teleportation of light beams
• Quantum teleportation with squeezed vacuum states
• Criteria for Continuous-Variable Quantum Teleportation
• Atomic Quantum State Teleportation and Swapping
• Quantum versus Classical Domains for Teleportation with Continuous Variables
• Quantum cloning at the light-atoms interface: copying a coherent light state into two atomic quantum memories
• Biased EPR entanglement and its application to teleportation
• Quantum Teleportation Using Quantum Non-Demolition Technique

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