We revisit a recently proposed scheme [M.F. Ciappina et al 2019 Phys. Rev. A 99 043405] for accurate measurement of electromagnetic radiation intensities in a focus of high-power laser beams. The method is based on the observation of multiple sequential tunneling ionization of atoms and suggests the determination of the peak intensity value from the appearance in the focal area ions with a certain charge number. Here we study the sensitivity of the approach to two essential factors: the focal volume effect and the tunneling ionization model chosen to calculate ionization rates. We show, on the one hand, that the results appear almost model-independent for ionization of helium- and hydrogen-like ions and, on the other hand, that the focal averaging leaves the intensity-dependent features visible. Our findings are in favor to a practical implementation of the atomic diagnostics of extreme laser intensities.

中文翻译：

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使用隧道电离诊断超强激光脉冲

我们重新审视了最近提出的方案 [MF Ciappina et al 2019 Phys. Rev. A 99 043405] 用于精确测量高功率激光束焦点处的电磁辐射强度。该方法基于对原子的多次连续隧穿电离的观察，并建议从具有一定电荷数的焦点区域离子中的出现来确定峰值强度值。在这里，我们研究了该方法对两个基本因素的敏感性：焦体积效应和选择用于计算电离率的隧道电离模型。我们表明，一方面，结果对于类氦和类氢离子的电离几乎与模型无关，另一方面，焦点平均使强度相关特征可见。