MT-FIMMPROP

Introduction

What is MT-FIMMPROP?

Multi Topology (MT-) FIMMPROP is a powerful simulation tool for simulating mode propagation through waveguide devices. MT-FIMMPROP expands the capabilities of Photon Design’s industry leading rigorous EigenMode Expansion (EME) method; from simulating coupling regions to entire PIC components.

MT-FIMMPROP completes what started in FIMMPROP, creating a fully schematic environment to act also as a layout tool. Once the design is complete, MT-FIMMPROP can now export your devices in a GDS II format.

Left: Schematic layout view of Long-Arm Mach-Zehnder Interferometer (MZI).
Right: Field intensity plotted along the MZI, simulated with EME.

MT-FIMMPROP is fully integrated into the FIMMWAVE environment, allowing for the use of established tools such as FIMMPROP variable scans, optimisation with Kallistos, and scripting support.

A Powerful and Versatile Optical Propagation Tool

The scale of many epitaxially grown waveguide devices such as those found in III-V integrated optics or silicon photonics can pose problems for conventional tools. Methods such as FDTD have long been resigned to simulate small coupling regions of devices, leaving designers to stitch many results together to approximate their full devices. With MT-FIMMPROP users will be able to model and simulate their entire devices in a single environment.

Computational Regions

MT-FIMMPROP is able to simulate these larger devices by not simulating the entire canvas but only the user defined computational regions. These come in two types:

• Path computational regions automatically conform to any path that has been defined. Waveguide paths and ridge widths can be defined through functions meaning arbitrary waveguides can be created. These can be added to a waveguide with a single click.

• Span computational regions are rectangular boxes that can be placed over multiple waveguide regions to simulate the coupling between them (shown in the 'pop-out' of the ring resonator figure below). Span regions are added with a simple click-and-drag to define the position and size of the box.

This innovation not only allows users to apply the EME method to a new domain of large devices, it also allows for efficiency gains to be found in pre-existing simulations that contain empty space such as Y-Splitters.

Double Ring Resonator: Computational Regions shown in hashed red.
'Pop-out' shows a span region to simulate coupling between the waveguides.

Want to Know More?

We look forward to sharing more examples and results as MT-FIMMPROP begins to role out. In the mean time, to learn more about MT-FIMMPROP you can read our brochure [View Brochure] or reach out and contact us for a demonstration of the software in action.