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arXiv · 2210.17120

Nonlinear feedforward enabling quantum computation

Atsushi Sakaguchi·Shunya Konno·Fumiya Hanamura·Warit Asavanant·Kan Takase·Hisashi Ogawa·Petr Marek·Radim Filip·Jun-ichi Yoshikawa·Elanor Huntington·Hidehiro Yonezawa·Akira Furusawa
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Abstract

Measurement-based quantum computation with optical time-domain multiplexing is a promising method to realize a quantum computer from the viewpoint of scalability. Fault tolerance and universality are also realizable by preparing appropriate resource quantum states and electro-optical feedforward that is altered based on measurement results. While a linear feedforward has been realized and become a common experimental technique, nonlinear feedforward was unrealized until now. In this paper, we demonstrate that a fast and flexible nonlinear feedforward realizes the essential measurement required for fault-tolerant and universal quantum computation. Using non-Gaussian ancillary states we observed 10$\%$ reduction of the measurement excess noise relative to classical vacuum ancilla.

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Atsushi Sakaguchi, Shunya Konno, Fumiya Hanamura, Warit Asavanant, Kan Takase, Hisashi Ogawa, Petr Marek, Radim Filip, Jun-ichi Yoshikawa, Elanor Huntington, Hidehiro Yonezawa, Akira Furusawa. 2022-10-31. Nonlinear feedforward enabling quantum computation. https://doi.org/10.1038/s41467-023-39195-w

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