论文标题
通过反射率测量对铝和钨的超短激光激发的研究
Investigation of ultrashort laser excitation of aluminum and tungsten by reflectivity measurements
论文作者
论文摘要
我们通过单个近红外激光脉冲激发了铝制的激光诱导的消融阈值，持续时间为15 fs至100 fs。两种金属的消融阈值均匀呈恒定，将相应的缩放指标扩展到几个光周期激光脉冲。同时，测量反射率，可在所研究材料中的脉冲持续时间和入射力范围以下和更高的裂纹阈值下方，从而在所研究的材料中访问沉积能量。开发了一种基于两个温度模型和Drude-Lorentz模型的模拟方法，以描述激发激发后固体（晶格和电子温度，反射率）的瞬时热力学和光学特性的演变。实验结果与模拟之间的对抗突出了考虑钨等过渡金属中状态密度的详细描述和演变的重要性。
We determine the laser-induced ablation threshold fluence in air of aluminum and tungsten excited by single near-infrared laser pulses with duration ranging from 15 fs to 100 fs. The ablation threshold fluence is shown constant for both metals, extending the corresponding scaling metrics to few-optical-cycle laser pulses. Meanwhile, the reflectivity is measured providing access to the deposited energy in the studied materials on a wide range of pulse durations and incident fluences below and above the ablation threshold. A simulation approach, based on the two-temperature model and the Drude-Lorentz model, is developed to describe the evolution of the transient thermodynamic and optical characteristics of the solids (lattice and electronic temperatures, reflectivity) following laser excitation. The confrontation between experimental results and simulations highlights the importance of considering a detailed description and evolution of the density of states in transition metals like tungsten.
