Quantum teleportation of light beams

Abstract

We experimentally demonstrate quantum teleportation for continuous variables using squeezed-state entanglement. The teleportation fidelity for a real experimental system is calculated explicitly, including relevant imperfection factors such as propagation losses, detection inefficiencies, and phase fluctuations. The inferred fidelity for input coherent states is $F=0.61\mathrm{}\pm 0.02,$ which when corrected for the efficiency of detection by the output observer, gives a fidelity of $\mathrm{0.62.}$ By contrast, the projected result based on the independently measured entanglement and efficiencies is $\mathrm{0.69.}$ The teleportation protocol is explained in detail, including a discussion on discrepancy between experiment and theory, as well as on the limitations of the current apparatus.