Nonlinearity of optimized silicon photonic slot waveguides

Abstract

In this numerical study, we show that by exploiting the advantages of the horizontal silicon slot wave-guide structure the nonlinear interaction can be significantly increased compared to vertical slot waveguides. The deposition of a 20 nm thin optically nonlinear layer with low refractive index sandwiched between two silicon wires of 220 nm width and 205 nm height could enable a nonlinearity coefficient gamma of more than 2 x 10(7) W(-1)km(-1).

Design Optimization of Silicon-on-Insulator Slot-Waveguides for Electro-optical Modulators and Biosensors

“…Figure 11.9 indicates that there is a threshold in the parameter range of our simulation of A eff ¼ 0:032 lm 2 for a slot width of s ¼ 80 nm and a rail width of w ¼ 225 nm. Also in this case our results are in good agreement with literature data [33]. …”

Low-Loss Slot Waveguides with Silicon (111) Surfaces Realized Using Anisotropic Wet Etching

“…Due to the discontinuity in the electric field at the high index contrast interfaces, such a structure supports an optical mode which can confine and guide light along the nanometer-size region of low index material, as shown in Figure 1. This unique property of slot waveguides has been exploited in many areas such as sensing (Barrios et al, 2007;Carlborg et al, 2010), non-linear optics (Muellner et al, 2009;Martínez et al, 2010), electro-optic modulation (Baehr-Jones et al, 2008;Chen et al, 2009;Koos et al, 2009), light sources (Guo et al, 2012;Tengattini et al, 2013), etc. However, a major limitation of slot waveguides is their high propagation loss.…”

Nonlinear Group IV photonics based on silicon and germanium: from near-infrared to mid-infrared

“…For example, when a nano-scale low-index layer is sandwiched between two high-index layers, a slot waveguide can be formed [43][44][45][46], with a large fraction of modal power trapped in the thin layer. Relative to many nonlinear materials such as SRO, SRN, chalcogenides, and polymers, silicon has a sufficiently large index to form a slot waveguide [47][48][49][50][51]. Moreover, adding a slot layer provides more design freedom to tailor chromatic dispersion, as reported in standard slot waveguides [51][52][53][54][55][56][57][58] and strip/ slot hybrid waveguides [59][60][61][62][63].…”