Physics and engineering of strong terahertz pulse generation
Terahertz science and technology is of great current interest due to its potential applications in bio-medical imaging and spectroscopy, chemical/explosive detection, wireless communication, security scanning, and plasma diagnostics. However, few sources and detectors exist in the terahertz frequency band. This leaves a major gap between the optical and microwave regions, for which new high-power terahertz sources would have a major impact. One promising source pioneered by my group and now adopted worldwide is based on controlling the laser-driven orbits of free electrons liberated by high field ionization of gases. In this talk, I will present recent experiments that provide a better understanding of this process, enabling us to achieve a world record in THz generation efficiency. This source will open up new opportunities to explore extreme terahertz-driven nonlinear processes in atoms, molecules, and plasmas.