Alkali-metal atomic magnetometers employing longitudinal carrier magnetic field have ultrahigh sensitivity to measure transverse magnetic fields and have been applied in a variety of precise-measurement science and technologies. In practice, the magnetometer response is not rigorously proportional to the measured transverse magnetic fields and the existing fundamental analytical model of this magnetometer is effective only when the amplitudes of the measured fields are very small. In this paper, we present a modified analytical model to characterize the practical performance of the magnetometer more definitely. We find out how the longitudinal magnetization of the alkali metal atoms vary with larger transverse fields. The linear-response capacity of the magnetometer is determined by these factors: the amplitude and frequency of the longitudinal carrier field, longitudinal and transverse spin relaxation time of the alkali spins and rotation frequency of the transverse fields. We give a detailed and rigorous theoretical derivation by using the perturbation-iteration method and simulation experiments are conducted to verify the validity and correctness of the proposed modified model. This model can be helpful for measuring larger fields more accurately and configuring a desirable magnetometer with proper linear range.

采用纵向载流子磁场的碱金属原子磁强计对横向磁场的测量具有超高灵敏度，已应用于多种精密测量科学和技术中。实际上，磁力计响应与测量的横向磁场不严格成正比，并且该磁力计的现有基本分析模型仅在测量场的幅度非常小时才有效。在本文中，我们提出了一种改进的分析模型，以更明确地表征磁力计的实际性能。我们发现碱金属原子的纵向磁化强度如何随着较大的横向场而变化。磁力计的线性响应能力由以下因素决定：纵向载流子场的幅度和频率，碱自旋的纵向和横向自旋弛豫时间以及横向场的旋转频率。我们使用扰动迭代法给出了详细而严谨的理论推导，并通过仿真实验验证了所提出的修正模型的有效性和正确性。该模型有助于更准确地测量更大的磁场并配置具有适当线性范围的理想磁力计。我们利用扰动迭代法给出了详细而严谨的理论推导，并通过仿真实验验证了所提出的修正模型的有效性和正确性。该模型有助于更准确地测量更大的磁场并配置具有适当线性范围的理想磁力计。我们使用扰动迭代法给出了详细而严谨的理论推导，并通过仿真实验验证了所提出的修正模型的有效性和正确性。该模型有助于更准确地测量更大的磁场并配置具有适当线性范围的理想磁力计。