We present upper bounds on the quantum and private capacity of single-mode, phase-insensitive bosonic Gaussian channels based on degradable extensions. Our findings are state of the art in the following parameter regions: low temperature and high transmissivity for the thermal attenuator, low temperature for additive Gaussian noise, high temperature and intermediate amplification for the thermal amplifier.

中文翻译：

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通过可降解扩展估计高斯信道的量子和私有容量

我们提出了基于可降解扩展的单模、相位不敏感玻色高斯通道的量子和私有容量的上限。我们的发现在以下参数区域是最先进的：热衰减器的低温和高透射率、附加高斯噪声的低温、热放大器的高温和中间放大。