X‐ray absorption spectroscopy of thin films is central to a broad range of scientific fields, and is typically detected using indirect techniques. X‐ray excited optical luminescence (XEOL) from the sample's substrate is one such detection method, in which the luminescence signal acts as an effective transmission measurement through the film. This detection method has several advantages that make it versatile compared with others, in particular for insulating samples or when a probing depth larger than 10 nm is required. In this work a systematic performance analysis of this method is presented with the aim of providing guidelines for its advantages and pitfalls, enabling a wider use of this method by the thin film community. The efficiency of XEOL is compared and quantified from a range of commonly used substrates. These measurements demonstrate the equivalence between XEOL and X‐ray transmission measurements for thin films. Moreover, the applicability of XEOL to magnetic studies is shown by employing XMCD sum rules with XEOL‐generated data. Lastly, it is demonstrated that above a certain thickness XEOL shows a saturation‐like effect, which can be modelled and corrected for.

中文翻译：

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使用基材发光检测的薄膜的软X射线吸收：性能分析。

薄膜的X射线吸收光谱学是广泛科学领域的核心，通常使用间接技术进行检测。样品基材的X射线激发光学发光（XEOL）是一种这样的检测方法，其中发光信号充当穿过薄膜的有效透射测量。与其他方法相比，该检测方法具有多种优势，使其具有通用性，特别是对于绝缘样品或需要大于10 nm的探测深度时。在这项工作中，对这种方法进行了系统的性能分析，目的是为其优点和缺陷提供指导，从而使薄膜社区可以更广泛地使用此方法。XEOL的效率可通过一系列常用底物进行比较和量化。这些测量证明了薄膜的XEOL和X射线透射测量之间的等效性。此外，通过将XMCD和规则与XEOL生成的数据结合使用，可以证明XEOL在磁性研究中的适用性。最后，证明了在一定厚度以上，XEOL表现出类似饱和的效果，可以对其进行建模和校正。