Easily adaptable and scalable semiconductor THz pulse source

A new type of scalable semiconductor THz source is proposed. It contains only two optical elements: a volume phase holographic grating, used at normal incidence to introduce the necessary pulse-front-tilt for phase matching, and a plane-parallel semiconductor crystal, such as GaP. Optical coupling between them is established by refractive index matching liquid. The setup is easily adaptable to different pump wavelengths (up to ~2.5 µm) and THz frequencies by changing the grating.