Non collinear phase matching sum frequency generation based on boundary total re

Collinear phase-matching of sum-frequency generation (SFG) has been studied thoroughly previously, while non-collinear schemes are sometimes more flexible in application. However, this phase-matching type is more difficult to meet and control. We employ a convenient method to obtain harmonic generation in bulk potassium dihydrogen phosphate (KDP), using an incident wave vector and a reflected wave vector to create a triangle phase-matching relationship. With a simple, flexible set-up, we can obs