The quantum phase noise in a pulsed semiconductor laser is studied thoroughly in the context of its utilization as a quantum entropy source in a quantum random number generator (QRNG) device. We performed a numerical analysis of the phase diffusion process for a semiconductor laser in the continuous-wave operation mode and gain-switched (GS) mode. The result demonstrates the amplification of randomness in the GS mode, which is gauged physically by the variance $Var\left[\mathrm{\Delta }\varphi \right]$. The variance value, which is mathematically related to the temporal distance between the laser pulses used in the experimental setup, also determines the stability of the setup. Furthermore, we show how the QRNG probability distribution is influenced by several experimental factors such as the quality of the interference process and the noise in the detection system.

中文翻译：

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用于量子随机数发生器中随机性评估的增益切换半导体激光器中相扩散过程的参数研究

脉冲半导体激光器中的量子相位噪声在其用作量子随机数发生器（QRNG）装置中的量子熵源的背景下进行了深入研究。我们对连续波工作模式和增益切换（GS）模式下半导体激光器的相扩散过程进行了数值分析。结果证明了GS模式下随机性的放大，这是通过方差物理衡量的$V\mathrm{一种}\mathrm{[R}\left[\mathrm{\Delta }\varphi \right]$。在数学上与实验装置中使用的激光脉冲之间的时间距离相关的方差值也确定了装置的稳定性。此外，我们展示了QRNG概率分布如何受到几个实验因素的影响，例如干扰过程的质量和检测系统中的噪声。