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The generation of an entangled four-photon state from two pairs of entangled two-photon states by using linear optical elements

XuBo Zou·K. Pahlke·W. Mathis
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Abstract

We present a scheme to produce an entangled four-photon state from two pairs of entangled two-photon states. Such entangled four-photon states are equivalent to the quantum state of two maximally entangled spin-1 particles. The scheme can also be generated to prepare an entangled 2N-photon state from N pairs of entangled two-photon states. Such multi-photon states play a crucial role in fundamental tests of quantum mechanics versus local realism and in many quantum information and quantum computation schemes.

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XuBo Zou, K. Pahlke, W. Mathis. 2001-12-14. The generation of an entangled four-photon state from two pairs of entangled two-photon states by using linear optical elements. https://arxiv.org/abs/quant-ph/0111014

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