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A Note on Linear Optics Gates by Post-Selection

E. Knill
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Abstract

Recently it was realized that linear optics and photo-detectors with feedback can be used for theoretically efficient quantum information processing. The first of three steps toward efficient linear optics quantum computation (eLOQC) was to design a simple non-deterministic gate, which upon post-selection based on a measurement result implements a non-linear phase shift on one mode. Here a computational strategy is given for finding non-deterministic gates for bosonic qubits with helper photons. A more efficient conditional sign flip gate is obtained.

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E. Knill. 2001-10-24. A Note on Linear Optics Gates by Post-Selection. https://doi.org/10.1103/physreva.66.052306

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