Non-maximally entangled states: production, characterization and utilization

Abstract

Using a spontaneous-downconversion photon source, we produce true non-maximally entangled states, i.e., without the need for post-selection. The degree and phase of entanglement are readily tunable, and are characterized both by a standard analysis using coincidence minima, and by quantum state tomography of the two-photon state. Using the latter, we experimentally reconstruct the reduced density matrix for the polarization. Finally, we use these states to measure the Hardy fraction, obtaining a result that is $122\sigma$ from any local-realistic result.

4 pages, 4 figures. To appear in Phys. Rev. Lett

References in corpus (1)

• Experimental quantum teleportation

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