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arXiv · 2404.19304

Boosting the generation rate of squeezed single-photon states by generalized photon subtraction

Hiroko Tomoda·Akihiro Machinaga·Kan Takase·Jun Harada·Takahiro Kashiwazaki·Takeshi Umeki·Shigehito Miki·Fumihiro China·Masahiro Yabuno·Hirotaka Terai·Daichi Okuno·Shuntaro Takeda
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Abstract

In optical quantum information processing with continuous variables, optical non-Gaussian quantum states are essential for universal and fault-tolerant quantum computation. Experimentally, their most typical generation method is photon subtraction (PS), where single-photon detection by an on/off detector probabilistically heralds the generation of squeezed single-photon states. In PS, however, trying to avoid unwanted multiphoton detection inevitably limits the generation rate, hindering the application of squeezed single-photon states. Here, we theoretically show that generalized photon subtraction (GPS), a simple extension of PS, can improve the generation rate while maintaining the quality of the generated states. Furthermore, we experimentally demonstrate the generation rate improvement for 2-dB- and 4-dB-squeezed single-photon states compared to PS, by more than one order of magnitude, particularly for the case of 2 dB. Our results will accelerate the application of squeezed single-photon states to more advanced quantum information protocols.

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Hiroko Tomoda, Akihiro Machinaga, Kan Takase, Jun Harada, Takahiro Kashiwazaki, Takeshi Umeki, Shigehito Miki, Fumihiro China, Masahiro Yabuno, Hirotaka Terai, Daichi Okuno, Shuntaro Takeda. 2024-04-30. Boosting the generation rate of squeezed single-photon states by generalized photon subtraction. https://doi.org/10.1103/physreva.110.033717

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