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 0\,Hz to provide a trigger photon. An optical cat state is created by applying the proposed 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 500\,MHz sideband modes shows the negativity of $W(0,0) = -0.088\pm0.001$ without any loss corrections.

中文翻译：

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在光学边带中产生猫状态

我们提出了一种从连续波光的双边带模式中减去光子的方法。中心思想是在先驱光子减法方案中将相位调制用作频率边带分束器，其中将一小部分边带模式下变频为0 \，Hz以提供触发光子。通过将所提出的方法应用于光参量振荡器产生的500MHz边带的压缩状态，可以创建光学猫状态。通过对500 \，MHz边带模式的直接零差测量重建的猫状态的Wigner函数显示$ W（0,0）= -0.088 \ pm0.001 $的负值，而无需进行任何损耗校正。