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arXiv · 1309.4724

State-dependent linear-optical qubit amplifier

Karol Bartkiewicz·Antonín Černoch·Karel Lemr
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Abstract

We propose a linear-optical setup for heralded qubit amplification with tunable output qubit fidelity. We study its success probability as a function of output qubit fidelity showing that at the expense of lower fidelity, the setup can considerably increase probability of successful operation. These results are subsequently applied in a proposal for state dependent qubit amplification. Similarly to state-dependent quantum cloning, the a priori information about the input state allows to optimize the qubit amplification procedure to obtain better fidelity versus success probability trade-off.

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Karol Bartkiewicz, Antonín Černoch, Karel Lemr. 2013-09-18. State-dependent linear-optical qubit amplifier. https://doi.org/10.1103/physreva.88.062304

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