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arXiv · 2301.09871

Non-Gaussian quantum state generation by multi-photon subtraction at the telecommunication wavelength

Mamoru Endo·Ruofan He·Tatsuki Sonoyama·Kazuma Takahashi·Takahiro Kashiwazaki·Takeshi Umeki·Sachiko Takasu·Kaori Hattori·Daiji Fukuda·Kosuke Fukui·Kan Takase·Warit Asavanant·Petr Marek·Radim Filip·Akira Furusawa
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Abstract

In the field of continuous-variable quantum information processing, non-Gaussian states with negative values of the Wigner function are crucial for the development of a fault-tolerant universal quantum computer. While several non-Gaussian states have been generated experimentally, none have been created using ultrashort optical wave packets, which are necessary for high-speed quantum computation, in the telecommunication wavelength band where mature optical communication technology is available. In this paper, we present the generation of non-Gaussian states on wave packets with a short 8-ps duration in the 1545.32 nm telecommunication wavelength band using photon subtraction up to three photons. We used a low-loss, quasi-single spatial mode waveguide optical parametric amplifier, a superconducting transition edge sensor, and a phase-locked pulsed homodyne measurement system to observe negative values of the Wigner function without loss correction up to three-photon subtraction. These results can be extended to the generation of more complicated non-Gaussian states and are a key technology in the pursuit of high-speed optical quantum computation.

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Mamoru Endo, Ruofan He, Tatsuki Sonoyama, Kazuma Takahashi, Takahiro Kashiwazaki, Takeshi Umeki, Sachiko Takasu, Kaori Hattori, Daiji Fukuda, Kosuke Fukui, Kan Takase, Warit Asavanant, Petr Marek, Radim Filip, Akira Furusawa. 2023-01-24. Non-Gaussian quantum state generation by multi-photon subtraction at the telecommunication wavelength. https://doi.org/10.1364/oe.486270

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