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arXiv · 1506.03896

Toward A Reconfigurable Quantum Network Enabled by a Broadband Entangled Source

E. Y. Zhu·C. Corbari·A. V. Gladyshev·P. G. Kazansky·H. K. Lo·L. Qian
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Abstract

We present a proof-of-principle experimental demonstration of a reconfigurable entanglement distribution scheme utilizing a poled fiber-based source of broadband polarization-entangled photon pairs and dense wavelength-division multiplexing. A large bandwidth (> 90 nm, centered at 1555 nm) and highly spectrally correlated nature of the entangled source can be exploited to allow for the generation of more than 25 frequency-conjugate entangled pairs when aligned to the standard 200 GHz ITU grid. In this work, three frequency-conjugate entangled pairs are used to demonstrate quantum key distribution, with the wavelength-selective switching done manually. The entangled pairs are delivered over 40 km of actual fiber, and an estimated secure key rate of up to 20 bits/s per bi-party is obtained.

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E. Y. Zhu, C. Corbari, A. V. Gladyshev, P. G. Kazansky, H. K. Lo, L. Qian. 2015-06-12. Toward A Reconfigurable Quantum Network Enabled by a Broadband Entangled Source. https://doi.org/10.1364/josab.36.0000b1

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