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arXiv · 1901.10939

Non-Gaussian quantum states of a multimode light field

Young-Sik Ra·Adrien Dufour·Mattia Walschaers·Clément Jacquard·Thibault Michel·Claude Fabre·Nicolas Treps
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Abstract

Even though Gaussian quantum states of multimode light are promising quantum resources due to their scalability, non-Gaussianity is indispensable for quantum technologies, in particular to reach quantum computational advantage. However, embodying non-Gaussianity in a multimode Gaussian state remains a challenge as controllable non-Gaussian operations are hard to implement in a multimode scenario. Here, we report the first generation of non-Gaussian quantum states of a multimode light field by subtracting a photon in a desired mode from multimode Gaussian states, and observe negativity of the Wigner function. For entangled Gaussian states, we observe that photon subtraction makes non-Gaussianity spread among various entangled modes. In addition to applications in quantum technologies, our results shed new light on non-Gaussian multimode entanglement with particular emphasis on quantum networks.

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Young-Sik Ra, Adrien Dufour, Mattia Walschaers, Clément Jacquard, Thibault Michel, Claude Fabre, Nicolas Treps. 2019-01-30. Non-Gaussian quantum states of a multimode light field. https://doi.org/10.1038/s41567-019-0726-y

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