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arXiv · 2105.13814

Wave-Shape-Tolerant Photonic Quantum Gates

Ihar Babushkin·Ayhan Demircan·Michael Kues·Uwe Morgner
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Abstract

Photons, acting as ``flying qubits'' in propagation geometries such as waveguides, appear unavoidably in the form of wavepackets (pulses). The actual shape of the photonic wavepacket, as well as possible temporal/spectral correlations between the photons, play a critical role in successful scalable computation. Currently, unentangled indistinguishable photons are considered as a suitable resource for scalable photonic circuits. Here we show that using so called coherent photon conversion, it is possible to construct flying-qubit gates, which are not only insensitive to waveshapes of the photons and temporal/spectral correlations between them, but which also fully preserve these waveshapes and correlations upon the processing. This allows using photons with correlations and purity in a very broad range for a scalable computation. Moreover, such gates can process entangled photonic wavepackets even more effectively than unentangled ones.

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Ihar Babushkin, Ayhan Demircan, Michael Kues, Uwe Morgner. 2021-05-28. Wave-Shape-Tolerant Photonic Quantum Gates. https://doi.org/10.1103/physrevlett.128.090502

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