Author Affiliations
Abstract
1 Shanghai Key Laboratory of Modern Optical System, Engineering Research Center of Optical Instrument and System, Ministry of Education, School of Optical-Electrical and Computer Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China
2 State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200062, China
Terahertz (THz) waves could be generated through exciting a gravity-guided, free-flowing water wedge by a dual-color pulse. It is not required to rotate the optimal angle considering the water film as an ionization medium. It is demonstrated to be more effective to generate stronger THz radiation when the ionization position is on the front surface of the air water interface of the water wedge by moving its position. The effect of pulse energy on THz generation is also investigated, and it is observed that with the increase of pulse energy the THz electric field shows a quadratic rising trend. These observations are consistent with air plasma induced THz emission.
water wedge THz plasma Chinese Optics Letters
2020, 18(7): 073201
上海理工大学光电信息与计算机工程学院, 上海 200093
利用太赫兹时域光谱技术测量了氧化铝和氢氧化铝样品在0.5~1.5 THz范围内的太赫兹时域电场信号。对测量得到的时域信号进行了傅里叶变换,得到了样品信号与参考信号频域的振幅和相位信息。对比参考信号的频域谱发现,氢氧化铝在1.20 THz和1.33 THz处有明显的特征峰,而氧化铝与参考信号频域谱的特征峰相同。通过对石墨烯与氢氧化铝进行一定比例的掺杂,利用石墨烯表面等离激元的近场增强效应,增强了分子内羟基的共振伸缩,实现了对氢氧化铝特征峰的增强调控。这项研究不仅可以对氢氧化铝进行无损检测和有效识别,也可以利用石墨烯增加氢氧化铝的检测灵敏度,对进一步利用太赫兹时域光谱技术研究其他氢氧化物的光谱信息具有借鉴意义。
光谱学 太赫兹时域光谱 氧化铝 氢氧化铝 石墨烯 等离激元 激光与光电子学进展
2019, 56(12): 123001
