Generation of high-frequency pulse train by designing a buried SOI waveguide

Abstract

Silicon photonics has attracted tremendous research interest in recent times because of its compact size, easy-to-build nature, and high values of nonlinearity. Though the study of pulse interaction inside a planer SOI waveguide is done earlier, the confinement of light should be better in the case of a buried core waveguide. Such a buried rectangular SOI waveguide is designed here, which possesses a small value of group velocity dispersion (β2) ∼2.432 (ps2/m) and a quite high value of nonlinear coefficient (γ) of ∼ 441.19 (W.m)−1. When the propagation of a pair of pulses of lower repetition rate (∼GHz) is investigated through it, we have found that the pulse pair interact with each other as they overlap and generate a high-frequency (∼THz) pulse train. The effect of timing jitter on high-frequency generation is also studied. The study of interactions of pulse pairs inside an SOI waveguide helps us to explore the potential applications of such devices as tunable high frequency (THz) pulse generators and many more.