THz generation in silicon photonics
Silicon waveguides functionalized with non-linear organic cladding material are a versatile integrated platform to provide long-range interaction of high-intensity confined light with non-linear material. We show that such waveguides can be utilized for high efficiency, integrated and compact THz sources. The concept is based on non-linear frequency mixing of two near infrared (NIR) modes guided in the same silicon waveguide that is cladded with non-linear organic polymers. Such materials can be well combined the with silicon photonic platform. In the non-linear cladding material, evanescent fields of the two NIR modes mix and produce the difference frequency which can be tuned to any frequency in the 1-10 THz range. This unique property makes such integrated THz sources suitable for applications in THz spectroscopy and THz imaging.