Mid-Infrared Nonlinear Frequency Conversion Using Monolithic Barium Titanate on Silicon-on-Insulator

nonlinear frequency conversion in the mid infrared (mid-IR) region was demonstrated by a barium titanate (BTO) on a silicon-on-insulator (SOI) substrate. The BTO thin film was epitaxially grown by pulsed-laser deposition (PLD). The tensorial second order optical nonlinearity and the ferroelectric domain property of the BTO were characterized by the polarimetric mid-IR second harmonic generation (SHG) measurements. Azimuthal dependent polarized SHG was modeled at different combinations of the nonlinear coefficient d(ij )and the domain fraction factor delta D-Y /delta D-X. Strong SHG intensity was experimentally observed over a broad spectrum at lambda = 3.1 mu m 3.7 mu m. A characteristic linear dependence between the SHG signal and the square of the pumping laser intensity was observed. The monolithic integration between the epitaxial BTO and the Si provides a compact platform for efficient on-chip light generation and quantum photonic technologies.

Automated summary

Nonlinear frequency conversion in the mid-infrared region was achieved using barium titanate (BTO) on a silicon-on-insulator (SOI) substrate. The BTO thin film was epitaxially grown using pulsed-laser deposition (PLD) and characterized through polarimetric mid-IR second harmonic generation (SHG) measurements. Strong SHG intensity was observed over a wide spectrum, providing a compact platform for efficient on-chip light generation and quantum photonic technologies.