High-Fidelity Teleportation of Independent Qubits

Abstract

Quantum teleportation is one of the essential primitives of quantum communication. We suggest that any quantum teleportation scheme can be characterized by its efficiency, i.e. how often it succeeds to teleport, its fidelity, i.e. how well the input state is reproduced at the output, and by its insensitivity to cross talk, i.e. how well it rejects an input state that is not intended to teleport. We discuss these criteria for the two teleportation experiments of independent qubits which have been performed thus far. In the first experiment (Nature {\bf 390},575 (1997)) where the qubit states were various different polarization states of photons, the fidelity of teleportation was as high as 0.80 $\pm$ 0.05 thus clearly surpassing the limit of 2/3 which can, in principle, be obtained by a direct measurement on the qubit and classical communication. This high fidelity is confirmed in our second experiment (Phys. Rev. Lett. {\bf 80}, 3891 (1998)), demonstrating entanglement swapping, that is, realizing the teleportation of a qubit which itself is still entangled to another one. This experiment is the only one up to date that demonstrates the teleportation of a genuine unknown quantum state.

13 pages, Latex, 5 figures(eps), to appear in Journal of Modern Optics

References in corpus (6)

• Experimental quantum teleportation
• Experimental Realization of Teleporting an Unknown Pure Quantum State via Dual Classical and Einstein-Podolski-Rosen Channels
• Violation of Bell's inequality under strict Einstein locality conditions
• A posteriori teleportation
• A posteriori teleportation ?
• Characterizing teleportation in optics

Cited by in corpus (14)

• Multi-photon entanglement and interferometry
• Feasible Entanglement Purification for Quantum Communication
• Experimental Four-photon Entanglement and High-fidelity Teleportation
• Information and Computation: Classical and Quantum Aspects
• Quantum-scissors device for optical state truncation: A proposal for practical realization
• Electron spin teleportation current through a quantum dot array operating in the stationary regime
• Verification of quantum-domain process using two non-orthogonal states
• Scale-invariant freezing of entanglement
• Optical qubit generation by state truncation using an experimentally feasible scheme
• Interferometric Tests of Teleportation
• Response in violation of Bell inequality to imperfect photon addition and subtraction in noisy squeezed states of light
• Distribution of Bell inequality violation vs. multiparty quantum correlation measures
• Swapping Intra-photon entanglement to Inter-photon entanglement using linear optical devices
• Fidelity of Fock-state-encoded qubits subjected to continuous variable Gaussian processes