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Practical creation and detection of polarization Bell states using parametric down-conversion

K. J. Resch·J. S. Lundeen·A. M. Steinberg
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Abstract

The generation and detection of maximally-entangled two-particle states, `Bell states,' are crucial tasks in many quantum information protocols such as cryptography and teleportation. Unfortunately, they require strong inter-particle interactions lacking in optics. For this reason, it has not previously been possible to perform complete Bell state determination in optical systems. In this work, we show how a recently developed quantum interference technique for enhancing optical nonlinearities can make efficient Bell-state measurement possible. We also discuss weaknesses of the scheme including why it cannot be used for unconditional quantum teleportation.

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K. J. Resch, J. S. Lundeen, A. M. Steinberg. 2002-04-05. Practical creation and detection of polarization Bell states using parametric down-conversion. https://doi.org/10.1142/9789812704634_0027

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