High harmonic generation - WikipediaFrom Wikipedia, the free encyclopedia Laser science process High-harmonic generation (HHG) is a non-linear process during which a target (gas, plasma, solid or liquid sample) is illuminated by an intense laser pulse. Under such conditions, the sample willen.wikipedia.org이 글에 대한 백그라운드 설명은 상기 위키디피아 링크를 참조해주세요. This is opposite to traditional optics theory in whi..