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Linear optical implementation of a single mode quantum filter and generation of multi-photon polarization entangled state

XuBo Zou·K. Pahlke·W. Mathis
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Abstract

We propose a scheme to implement a single-mode quantum filter, which selectively eliminates the one-photon state in a quantum state $α|0>+β|1>+γ|2>$. The vacuum state and the two photon state are transmitted without any change. This scheme requires single-photon sources, linear optical elements and photon detectors. Furthermore we demonstrate, how this filter can be used to realize a two-qubit projective measurement and to generate multi-photon polarization entangled states.

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XuBo Zou, K. Pahlke, W. Mathis. 2002-10-12. Linear optical implementation of a single mode quantum filter and generation of multi-photon polarization entangled state. https://doi.org/10.1103/physreva.66.064302

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