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arXiv · 1804.08905

Schr\"odinger's cat in an optical sideband

Takahiro Serikawa·Jun-ichi Yoshikawa·Shuntaro Takeda·Hidehiro Yonezawa·Timothy C. Ralph·Elanor H. Huntington·Akira Furusawa
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Abstract

We propose a method to subtract a photon from a double sideband mode of continuous-wave light. The central idea is to use phase modulation as a frequency sideband beamsplitter in the heralding photon subtraction scheme, where a small portion of the sideband mode is downconverted to the carrier frequency to provide a trigger photon. An optical Schr\"odinger's cat state is created by applying the propesed method to a squeezed state at 500MHz sideband, which is generated by an optical parametric oscillator. The Wigner function of the cat state reconstructed from a direct homodyne measurement of the 500MHz sideband modes shows the negativity of $W(0,0) = -0.088\pm0.001$ without any loss corrections.

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Takahiro Serikawa, Jun-ichi Yoshikawa, Shuntaro Takeda, Hidehiro Yonezawa, Timothy C. Ralph, Elanor H. Huntington, Akira Furusawa. 2018-04-24. Schr\"odinger's cat in an optical sideband. https://doi.org/10.1103/physrevlett.121.143602

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