Observation of broadband terahertz wave generation from liquid water
Abstract
Bulk liquid water is a strong absorber in the terahertz (THz) frequency range, due to which liquid water has historically been sworn off as a source for THz radiation. Here, we experimentally demonstrate the generation of broadband THz waves from liquid water excited by femtosecond laser pulses. Our measurements reveal the critical dependence of the THz field upon the relative position between the water film and the focal point of the laser beam. The THz radiation from liquid water shows distinct characteristics when compared with the THz radiation from air plasmas with single color optical excitation. First, the THz field is maximized with the laser beam of longer pulse durations. In addition, the p-polarized component of the emitted THz waves will be influenced by the polarization of the optical excitation beam. It is also shown that the energy of the THz radiation is linearly dependent on the excitation pulse energy.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Aug 14, 2017
- Source ID
- 10.1063/1.4990824
Entities
People
- Jianming Dai
- Kaia Williams
- Qi Jin
- X.-C. Zhang
- Yiwen E
Organizations
- Army Research Office
- Capital Normal University
- Huazhong University of Science and Technology
- Saint Petersburg State University of Information Technologies, Mechanics and Optics
- Tianjin University
- University of Rochester