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arXiv · 0710.0980

Preparation of entangled states of two photons in several spatial modes

Karel Lemr·Jaromir Fiurasek
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Abstract

We describe a protocol capable of preparing an arbitrary state of two photons in several spatial modes using pairs of photons generated by spontaneous parametric down-conversion, linear optical elements and single-photon detectors or post-selection. The protocol involves unitary and non-unitary transformations realizable by beam splitters and phase shifters. Non-unitary transformations are implemented by attenuation filters. The protocol contains several optimization capabilities with the goal of improving overall probability of its success. We also show how entangled two-photon states required for quantum computing with linear optics can be prepared using a very simple and feasible scheme.

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Karel Lemr, Jaromir Fiurasek. 2007-10-04. Preparation of entangled states of two photons in several spatial modes. https://doi.org/10.1103/physreva.77.023802

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