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arXiv · 1702.03336

Temporal-mode measurement tomography of a quantum pulse gate

Vahid Ansari·Georg Harder·Markus Allgaier·Benjamin Brecht·Christine Silberhorn
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Abstract

Encoding quantum information in the photon temporal mode (TM) offers a robust platform for high-dimensional quantum protocols. The main practical challenge, however, is to design a device that operates on single photons in specific TMs and all coherent superpositions. The quantum pulse gate (QPG) is a mode-selective sum-frequency generation designed for this task. Here, we perform a full modal characterisation of a QPG using weak coherent states in well-defined TMs. We reconstruct a full set of measurement operators, which show an average fidelity of 0.85 to a theoretically ideal device when operating on a 7-dimensional space. Then we use these characterised measurement operators of the QPG to calibrate the device. Using the calibrated device and a tomographically complete set of measurements, we show that the QPG can perform high-dimensional TM state tomography with 0.99 fidelity.

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Vahid Ansari, Georg Harder, Markus Allgaier, Benjamin Brecht, Christine Silberhorn. 2017-12-14. Temporal-mode measurement tomography of a quantum pulse gate. https://doi.org/10.1103/physreva.96.063817

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