Parameter Space Exploration in Dispersion Engineering of Multilayer Silicon Waveguides from Near-Infrared to Mid-Infrared

摘要

Dispersion engineering is important in integrated photonics with a high index contrast. We present an exploration of the parameter space in dispersion-engineered silicon multilayer waveguides, based on a strip/slot hybrid waveguide structure. The relationship between low-dispersion bandwidth and dispersion variation is extensively investigated under different index contrasts between silicon and slot material and various structural parameter sets. Our results show that with a refractive index ranging from 1.4 to 2.9, any real material can be used in combination with silicon for dispersion flattening in principle, as long as device fabrication technologies allow. This paper provides a general guideline for future designs of dispersion-flattened silicon waveguides. Ultrawide low dispersion with a dispersion variation of around ±35 ps/(nm·km) can be obtained over a 2000-nm wavelength range, from the near-infrared to the mid-infrared.