Preference of subpicosecond laser pulses for terahertz wave generation from liquids
Preference of subpicosecond laser pulses for terahertz wave generation from liquids
复制标题
DOI：
10.1117/1.ap.2.1.015001
复制
发表时间：
2020-01-01
影响因子：
17.3
通讯作者：
Zhang, Xi-Cheng
中科院分区：
文献类型：
--
作者：
Jin, Qi;Yiwen, E.;Zhang, Xi-Cheng
从激光诱导空气等离子体产生太赫兹（THz）波通常需要短时间的激光脉冲。相比之下，观察到来自离子化液态水的THz辐射更喜欢较长的脉冲，其中机制仍不清楚。我们属性的偏好较长的脉冲持续时间的电离和等离子体在水中形成的过程中，这是支持的数值模拟结果表明，最高的电子密度是实现与亚皮秒脉冲。当水的厚度变化时，我们的实验结果与模拟结果的一致性进一步验证了这一解释。其他液体也进行了测试，以确保这种脉冲的偏好不限于水。
Terahertz (THz) wave generation from laser-induced air plasma generally requires a short temporal laser pulse. In contrast, it was observed that THz radiation from ionized liquid water prefers a longer pulse, wherein the mechanism remains unclear. We attribute the preference for longer pulse duration to the process of ionization and plasma formation in water, which is supported by a numerical simulation result showing that the highest electron density is achieved with a subpicosecond pulse. The explanation is further verified by the coincidence of our experimental result and simulation when the thickness of the water is varied. Other liquids are also tested to assure the preference for such a pulse is not exclusive to water.