🎯 Learning objectives

Construct a 2D slab waveguide model in OghmaNano by defining X and Y optical meshes.
Set wavelength sampling and mesh resolution to capture mode behaviour accurately.
Run 2D mode calculations and visualise field distributions in the snapshots viewer.
Use eigenmode search parameters (X/Y indices) to control and target specific modes.
Compare TE and TM solutions in 2D and recognise characteristic features such as interface discontinuities.

📦 Prerequisites

OghmaNano installed and working.
Basic familiarity with refractive index and guided modes.

⏱ Estimated time

Part A (1D TE/TM): 10–15 min
Part B (2D modes): 10–15 min
Part C (2D complex modes): 10–15 min

2D slab waveguide mode solver (TE/TM)

In this tutorial we calculate the guided optical modes supported by 2D slab waveguide structures using the OghmaNano optical mode solver. The tutorial demonstrates how to construct optical meshes, solve transverse electric (TE) and transverse magnetic (TM) eigenmodes, and visualise confined optical field distributions in dielectric waveguides.

OghmaNano Optical ribbon showing the Optical mesh button highlighted. — Click the **Optical mesh** button in the **Optical ribbon** to open the *Optical mesh editor*. The button is highlighted in the red box above.

OghmaNano Optical Mesh Editor showing the Y-dimension mesh with wavelength points. — The **Optical Mesh Editor** showing the *1D mesh* in the Y direction. If you click on the **X button** in the toolbar, the X-dimension mesh can also be edited.

OghmaNano Optical Mesh Editor showing both X and Y dimension meshes with wavelength points. — After adding the **X mesh** and setting the number of mesh points to 20, both the X and Y meshes are defined, enabling a full 2D optical mesh.

1. Constructing a 2D slab waveguide

Open New simulation → Mode solvers and select the 1D slab waveguide example. Configure the layer stack (e.g., 500 nm / 500 nm / 500 nm) and refractive indices (n = 1 / 4 / 1 for cladding / core / cladding in this example). Set polarization to Transverse electric (TE).

OghmaNano Output tab showing the snapshots folder after a simulation has been run. — The **Output** tab after running the simulation. Here the **snapshots** folder is available — double-click it to open the snapshots viewer.

The Snapshots window displaying the calculated electric field distribution in the slab waveguide. By clicking the Add button and selecting Electric field, the 2D field profile is shown.

👉 Next step: Now continue to Part C for a more detailed OPV tutorial, including outputs, device layers, and advanced analysis.