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arXiv · 1409.0831

Quantum storage of entangled telecom-wavelength photons in an erbium-doped optical fibre

Erhan Saglamyurek·Jeongwan Jin·Varun B. Verma·Matthew D. Shaw·Francesco Marsili·Sae Woo Nam·Daniel Oblak·Wolfgang Tittel
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Abstract

The realization of a future quantum Internet requires processing and storing quantum information at local nodes, and interconnecting distant nodes using free-space and fibre-optic links. Quantum memories for light are key elements of such quantum networks. However, to date, neither an atomic quantum memory for non-classical states of light operating at a wavelength compatible with standard telecom fibre infrastructure, nor a fibre-based implementation of a quantum memory has been reported. Here we demonstrate the storage and faithful recall of the state of a 1532 nm wavelength photon, entangled with a 795 nm photon, in an ensemble of cryogenically cooled erbium ions doped into a 20 meter-long silicate fibre using a photon-echo quantum memory protocol. Despite its currently limited efficiency and storage time, our broadband light-matter interface brings fibre-based quantum networks one step closer to reality. Furthermore, it facilitates novel tests of light-matter interaction and collective atomic effects in unconventional materials.

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Erhan Saglamyurek, Jeongwan Jin, Varun B. Verma, Matthew D. Shaw, Francesco Marsili, Sae Woo Nam, Daniel Oblak, Wolfgang Tittel. 2015-01-13. Quantum storage of entangled telecom-wavelength photons in an erbium-doped optical fibre. https://doi.org/10.1038/nphoton.2014.311

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