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arXiv · 1608.05106

Overcoming experimental limitations in a non-linear two-qubit gate through postselection

Julián Martínez-Rincón
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Abstract

We introduce a modular-value two-qubit gate and explore its advantages in experimentally-limited situations. The gate is defined such that the final state of a target qubit is fully controlled by a pre- and post-selection procedure in a control qubit given an (imperfect or technically limited) intermediate conditional qubit-qubit interaction. As an example of the gate and its benefit, we make the connection to a postselected cross phase modulation scenario when a undesired absorption is present. Probabilistic amplification of a small cross phase while mitigating relative absorption is possible, and a complementary behaviour between phase and amplitude emerges.

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Julián Martínez-Rincón. 2016-10-27. Overcoming experimental limitations in a non-linear two-qubit gate through postselection. https://doi.org/10.1007/s11128-016-1485-7

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