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arXiv · 1309.3202

Spectral multiplexing for scalable quantum photonics using an atomic frequency comb quantum memory and feed-forward control

Neil Sinclair·Erhan Saglamyurek·Hassan Mallahzadeh·Joshua A. Slater·Mathew George·Raimund Ricken·Morgan P. Hedges·Daniel Oblak·Christoph Simon·Wolfgang Sohler·Wolfgang Tittel
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Abstract

Future multi-photon applications of quantum optics and quantum information science require quantum memories that simultaneously store many photon states, each encoded into a different optical mode, and enable one to select the mapping between any input and a specific retrieved mode during storage. Here we show, with the example of a quantum repeater, how to employ spectrally-multiplexed states and memories with fixed storage times that allow such mapping between spectral modes. Furthermore, using a Ti:Tm:LiNbO3 waveguide cooled to 3 Kelvin, a phase modulator, and a spectral filter, we demonstrate storage followed by the required feed-forward-controlled frequency manipulation with time-bin qubits encoded into up to 26 multiplexed spectral modes and 97% fidelity.

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Neil Sinclair, Erhan Saglamyurek, Hassan Mallahzadeh, Joshua A. Slater, Mathew George, Raimund Ricken, Morgan P. Hedges, Daniel Oblak, Christoph Simon, Wolfgang Sohler, Wolfgang Tittel. 2014-07-18. Spectral multiplexing for scalable quantum photonics using an atomic frequency comb quantum memory and feed-forward control. https://doi.org/10.1103/physrevlett.113.053603

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