Measurement sensitivity is one of the critical indicators for Rydberg atomic radio receivers. This work quantitatively studies the relationship between the atomic superheterodyne receiver’s sensitivity and the number of atoms involved in the measurement. The atom number is changed by adjusting the length of the interaction area. The results show that for the ideal case where only interaction noise is present and the RF waves are uniformly distributed, the sensitivity of the atomic superheterodyne receiver exhibits a quantum scaling: the amplitude of its output signal is proportional to the atom number, and the amplitude of its read-out noise is proportional to the square root of the atom number. Hence, its sensitivity is inversely proportional to the square root of the atom number. This work also gives a detailed discussion of the properties of transit noise in atomic receivers and the influence of some non-ideal factors on sensitivity scaling. This work is significant in the field of atom-based quantum precision measurements.

中文翻译：

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量子标度原子超外差接收器

测量灵敏度是里德堡原子无线电接收机的关键指标之一。这项工作定量研究了原子超外差接收器的灵敏度与参与测量的原子数量之间的关系。通过调节相互作用区域的长度来改变原子序数。结果表明，在仅存在相互作用噪声且射频波均匀分布的理想情况下，原子超外差接收器的灵敏度表现出量子标度：其输出信号的幅度与原子数成正比，幅度与原子数成正比。其读出噪声的大小与原子数的平方根成正比。因此，其灵敏度与原子数的平方根成反比。这项工作还详细讨论了原子接收器中传输噪声的特性以及一些非理想因素对灵敏度缩放的影响。这项工作在基于原子的量子精密测量领域具有重要意义。