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arXiv · 1503.06187

Scheme for a linear-optical controlled-phase gate with programmable phase shift

Karel Lemr·Karol Bartkiewicz·Antonín Černoch
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Abstract

We present a linear-optical scheme for a controlled-phase gate with tunable phase shift programmed by a qubit state. In contrast to all previous tunable controlled-phase gates, the phase shift is not hard-coded into the optical setup, but can be tuned to any value from 0 to pi by the state of a so-called program qubit. Our setup is feasible with current level of technology using only linear-optical components. We provide an experimental feasibility study to assess the gate's implementability. We also discuss options for increasing the success probability up to 1/12 which approaches the success probability of a optimal non-programmable tunable controlled-phase gate.

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Karel Lemr, Karol Bartkiewicz, Antonín Černoch. 2015-06-02. Scheme for a linear-optical controlled-phase gate with programmable phase shift. https://doi.org/10.1088/2040-8978%2F17%2F12%2F125202

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