Temnov V V, Sokolowski-Tinten K, Zhou P, El-Khamhawy A, von der Linde D
Institut für Experimentelle Physik, Universität Duisburg-Essen, 47048 Duisburg, Germany.
Phys Rev Lett. 2006 Dec 8;97(23):237403. doi: 10.1103/PhysRevLett.97.237403.
Ionization mechanisms in bulk dielectrics irradiated by single intense 50-fs-laser pulses are investigated by ultrafast time-resolved imaging interferometry. Polarization-sensitive 6-photon ionization is shown to be the dominant ionization mechanism in fused silica and sapphire at intensities around 10 TW/cm2. For both materials the cross sections of 6-photon ionization are found to be significantly higher for linear polarization than for circular. Our experimental results corroborate an earlier theoretical prediction on the dominance of linear polarization in high-order multiphoton ionization.
通过超快时间分辨成像干涉测量法研究了单个强50飞秒激光脉冲辐照块状电介质中的电离机制。在强度约为10太瓦/平方厘米时，偏振敏感的6光子电离被证明是熔融石英和蓝宝石中的主要电离机制。对于这两种材料，发现线性偏振的6光子电离截面明显高于圆偏振。我们的实验结果证实了早期关于高阶多光子电离中线性偏振占主导地位的理论预测。
