Slot Waveguide Design

4/7/2022

perraleta1981.netlify.com › Slot Waveguide Design ▀ ▀

Slot Waveguide Design 3,6/5 6819 votes

Waveguide Design Equations
Waveguide-slot Array Antenna Designs For Low-average-sidelobe Specifications
Waveguide Antenna

An optimal design of a slot waveguide is presented for realizing an ultrafast optical modulator based on a 220 nm silicon wafer technology. The recipe is to maximize the confinement and interaction between optical power supported by the waveguide and electric field applied through metallic electrodes.
Slotted Waveguide Array Antennas is the first comprehensive treatment of these antennas from an engineering perspective. It provides readers with a thorough foundation in applicable theories as well as hands-on instruction for practical analysis, design, manufacture and use of important types of waveguide slot.

Modes of Slot Waveguides

Omnidirectional Sector Waveguide SLOT Antenna L and C Band (1296 & 2320 MHz) The slotted waveguide has achieved most of its success when used in an omnidirectional role. It is the simplest way to get a real 10dB gain over 360 degrees of beamwidth. The Slotted waveguide antenna is a Horizontally Polarized type antenna and light in weight. 3 Tuning screws are placed for tweaking the SWR and can. The following lines show the design and simulation of a Slot Waveguide Array Antenna (SWAA) for satellite communications in the 30 GHz band. The antenna will be approximately 170x170 mm, constituted by 24x24 slots. It will be fed by waveguides in a lower layer connected to the radiating guides through slots.

Simulation of silicon cross-slot waveguide with FIMMWAVE software

FIMMWAVE's mode solvers were used to calculate the modes of a silicon cross-slot waveguide; slot waveguides use a combination of high-index and low-index layers to generate light confinement.

FIMMWAVE can be used to model any slot waveguide geometry built from any materials, including silicon, polymer and hybrid slot waveguides. The silicon cross-slot waveguide presented here is taken from an article from Helsinki University of Technology [1], featuring FIMMWAVE simulations. The paper also presents results for waveguide geometries with angled sidewalls.

See also [2], also featuring FIMMWAVE simulations for the modelling of slot waveguides.

Silicon slot waveguide designed in FIMMWAVE

The modes of the silicon slot waveguide were calculated using FIMMWAVE's fully vectorial FDM Solver. The calculation only took a few seconds, and the solver was able to take advantage of the waveguide symmetry.

This waveguide is a single-mode waveguide, and the fundamental TE-like mode and TM-like mode are shown below. You can see clearly how the cross-slot geometry generates a 90-degree rotation of the field distribution between the two polarisations. FIMMWAVE can also provide a large number of mode properties, including effective index, propagation constant, group index, dispersion, polarisation, effective mode area, confinement factor etc.

Properties of the fundamental TE-like mode of the silicon cross-slot waveguide:
(clockwise from top-left) intensity profile, Ex field profile and horizontal section, mode properties

Properties of the fundamental TM-like mode of the silicon cross-slot waveguide:
(clockwise from top-left) intensity profile, Ey field profile and horizontal section, mode properties

FIMMWAVE allows you to check the accuracy of your calculation as it features three independent fully-vectorial Cartesian mode solvers: the FMM, FDM and FEM Solvers. We ran the simulation with all three solvers and found the results to be in excellent agreement.

FIMMPROP, the propagation tool associated with FIMMWAVE, can also be used to model light propagating within slot-waveguide structures.

References

[1] A. Khanna, A. Säynätjoki, A. Tervonen and S. Honkanen, 'Control of optical mode properties in cross-slot waveguides', Applied Optics 48, 34, pp. 6547-6552 (2009)

[2] M.P. Hiscocks, C. Su, B. Gibson, A.D. Greentree, L.C.L. Hollenberg, and F. Ladouceur, 'Slot-waveguide cavities for optical quantum information applications', Optics Express 17, 9, p7295-7303 (2009)

More publications

Click here to find publications that include FIMMWAVE simulations of slot waveguides on Google Scholar.

Optics Letters
Vol. 41,
Issue 11,
pp. 2501-2504
(2016)
•https://doi.org/10.1364/OL.41.002501

Get Citation
Copy Citation Text
Abhijeet Phatak, Zhenzhou Cheng, Changyuan Qin, and Keisuke Goda, 'Design of electro-optic modulators based on graphene-on-silicon slot waveguides,' Opt. Lett. 41, 2501-2504 (2016)
Export Citation

Abstract

We present a graphene-on-silicon (GoS) suspended vertical slot waveguide. By changing the Fermi level of graphene, the variation in the effective refractive index (RI) of the waveguide is a factor of two larger than that in the traditional GoS rib waveguide. The improvement is due to the light-intensity enhancement and the poor confinement of the optical mode in the slot nanostructure. We design Mach–Zehnder interferometer (MZI) and microring modulators based on the GoS suspended vertical slot waveguide. Our calculations show that the modulators can be energy-efficient and footprint-compact due to the large phase shift of the propagating mode in the waveguide after applying a gate voltage on the graphene. Fabrication of our design is easy and CMOS-compatible. It paves the way for chip-integrated electronic-RI modulators.

Full Article PDF ArticleOSA Recommended ArticlesDesign of graphene-on-germanium waveguide electro-optic modulators at the 2μm wavelength Slot Waveguide Design

Jiaqi Wang, Qiuxia Li, Dan Huang, Chongbin Liang, Yuzhi Chen, Lin Fang, Youfu Geng, Xueming Hong, and Xuejin Li
OSA Continuum 2(3) 749-758 (2019)

One-dimensional photonic crystal slot waveguide for silicon-organic hybrid electro-optic modulators

Waveguide Design Equations

Hai Yan, Xiaochuan Xu, Chi-Jui Chung, Harish Subbaraman, Zeyu Pan, Swapnajit Chakravarty, and Ray T. Chen
Opt. Lett. 41(23) 5466-5469 (2016)

Nanoscale electro-optic modulators based on graphene-slot waveguides

Zhaolin Lu and Wangshi Zhao
J. Opt. Soc. Am. B 29(6) 1490-1496 (2012)

References

You do not have subscription access to this journal. Citation lists with outbound citation links are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.