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arXiv · 1507.03210

Heralded amplification of photonic qubits

Natalia Bruno·Vittorio Pini·Anthony Martin·Boris Korzh·Félix Bussières·Varun Verma·Sae Woo Nam·Richard Mirin·Adriana Lita·Francesco Marsili·Nicolas Sangouard·Hugo Zbinden·Nicolas Gisin·Robert Thew
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Abstract

We demonstrate heralded qubit amplification for Time-Bin and Fock-state qubits in an all-fibre, telecom-wavelength, scheme that highlights the simplicity, the stability and potential for fully integrated photonic solutions. Exploiting high-efficiency superconducting detectors, the gain, the fidelity and the performance of the amplifier are studied as a function of loss. We also demonstrate the first heralded Fock-state qubit amplifier without post-selection. This provides a significant advance towards demonstrating Device-Independent Quantum Key Distribution as well as fundamental tests of quantum mechanics over extended distances.

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Natalia Bruno, Vittorio Pini, Anthony Martin, Boris Korzh, Félix Bussières, Varun Verma, Sae Woo Nam, Richard Mirin, Adriana Lita, Francesco Marsili, Nicolas Sangouard, Hugo Zbinden, Nicolas Gisin, Robert Thew. 2015-07-12. Heralded amplification of photonic qubits. https://doi.org/10.1364/oe.24.000125

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