EMode plugin

Makefile

@@ -6,7 +6,7 @@ venv:
 
 install:
 	uv venv --python 3.11
-	uv pip install -e .[dev,docs,femwell,gmsh,meow,sax,tidy3d,klayout,vlsir]
+	uv pip install -e .[dev,docs,femwell,gmsh,meow,sax,tidy3d,klayout,vlsir,emode]
 	uv run pre-commit install
 
 dev: test-data gmsh elmer install

README.md

@@ -24,10 +24,12 @@ Run simulations with GDSFactory by installing plugins.
         - `palace` for full-wave driven (S parameter) and electrostatic (capacitive) simulations.
     - EME
         - `meow` Eigen Mode Expansion (EME).
+        - `EMode`
     - Mode Solver
         - Tidy3d
         - Femwell
         - MPB
+        - `EMode`
     - TCAD
         - `devsim` TCAD device simulator.
 - Circuit simulations
@@ -46,7 +48,7 @@ pip install "gdsfactory[full]" --upgrade
 Or list the plugins individually:
 
 ```bash
-pip install "gplugins[devsim,femwell,gmsh,schematic,meow,meshwell,sax,tidy3d]" --upgrade
+pip install "gplugins[devsim,femwell,gmsh,schematic,meow,meshwell,ray,sax,tidy3d,emode]" --upgrade
 ```
 
 Or install only the plugins you need. For example:

docs/_toc.yml

@@ -32,6 +32,7 @@ parts:
           - file: notebooks/mode_solver_fdfd
           - file: notebooks/mpb_001_mpb_waveguide
           - file: notebooks/meow_01
+          - file: notebooks/emode
       - file: plugins_fdtd
         sections:
           - file: notebooks/tidy3d_00_tidy3d

docs/plugins_mode_solver.md

@@ -2,14 +2,18 @@
 
 A mode solver computes the modes supported by a waveguide cross-section at a particular wavelength. Modes are definite-frequency eigenstates of Maxwell's equations.
 
-You can use 3 open source mode solvers:
+You can use several mode solvers with GDSFactory:
 
-1. tidy3d. Finite difference Frequency Domain (FDFD).
-2. MPB. FDFD with periodic boundary conditions.
-3. Femwell. Finite Element (FEM).
+**Open Source:**
+- ``tidy3d``: Finite difference Frequency Domain (FDFD).
+- ``MPB``: FDFD with periodic boundary conditions.
+- ``Femwell``: Finite Element (FEM).
+- ``meow``: The tidy3d mode solver is also used by the MEOW plugin to get the Sparameters of components via Eigenmode Expansion.
 
-The tidy3d mode solver is also used by the MEOW plugin to get the Sparameters of components via Eigenmode Expansion.
-Notice that the tidy3d FDTD solver is not open source as it runs on the cloud server, but the mode solver is open source and runs locally on your computer.
+    **Notice**: The tidy3d FDTD solver is not open source as it runs on the cloud server, but the mode solver is open source and runs locally on your computer.
+
+**Proprietary:**
+- ``EMode``: A versatile waveguide mode solver using the Finite-Difference Frequency Domain (FDFD) method, and a propagation tool using the Eigenmode Expansion method (EME). Requires the EMode software suite to be installed separately. See [docs.emodephotonix.com/installation](https://docs.emodephotonix.com/installation) for installation instructions.
 
 ```{tableofcontents}
 ```

gplugins/emode/__init__.py

@@ -0,0 +1,4 @@
+from emodeconnection import open_file, get, inspect
+from .utils import EMode
+
+__all__ = ["EMode", "open_file", "get", "inspect"]

gplugins/emode/tests/SOI.py

@@ -0,0 +1,60 @@
+
+import gplugins.emode as emc
+from gdsfactory.cross_section import rib
+from gdsfactory.generic_tech import LAYER_STACK
+from gdsfactory.technology import LayerStack
+
+
+## Set up GDSFactory LayerStack and CrossSection in units of microns
+layer_stack = LayerStack(
+    layers={
+        k: LAYER_STACK.layers[k]
+        for k in (
+            "core",
+            "clad",
+            "slab90",
+            "box",
+        )
+    }
+)
+
+layer_stack.layers["core"].thickness = 0.22
+layer_stack.layers["core"].zmin = 0
+
+layer_stack.layers["slab90"].thickness = 0.09
+layer_stack.layers["slab90"].zmin = 0
+
+layer_stack.layers["box"].thickness = 1.5
+layer_stack.layers["box"].zmin = -1.5
+
+layer_stack.layers["clad"].thickness = 1.5
+layer_stack.layers["clad"].zmin = 0
+
+## Connect and initialize EMode
+em = emc.EMode()
+
+## build_waveguide converts units to nanometers, which EMode's default
+modes = em.build_waveguide(
+    cross_section=rib(width=0.6),
+    layer_stack=layer_stack,
+    wavelength=1.55,
+    num_modes=1,
+    x_resolution=0.010,
+    y_resolution=0.010,
+    window_width = 3.0,
+    window_height = 3.0,
+    background_refractive_index='Air',
+    max_effective_index=2.631,
+)
+
+## Launch FDM solver
+em.FDM()
+
+## Display the effective indices, TE fractions, and core confinement
+em.report()
+
+## Plot the field and refractive index profiles
+em.plot()
+
+## Close EMode
+em.close()

gplugins/emode/utils.py

@@ -0,0 +1,72 @@
+import emodeconnection as emc
+from gdsfactory import CrossSection
+from gdsfactory.technology import LayerStack
+
+class EMode(emc.EMode):
+    def build_waveguide(
+        self,
+        cross_section: CrossSection,
+        layer_stack: LayerStack,
+        **kwargs,
+    ) -> None:
+        """Builds a waveguide structure in EMode based on GDSFactory CrossSection and LayerStack.
+
+        Args:
+            cross_section: A GDSFactory CrossSection object defining the waveguide's geometry.
+            layer_stack: A GDSFactory LayerStack object defining the material layers.
+            **kwargs: Additional keyword arguments to be passed directly to EMode's settings() function.
+        """
+        nm = 1e3 # convert microns to nanometers
+        dim_keys = [
+            'wavelength',
+            'x_resolution',
+            'y_resolution',
+            'window_width',
+            'window_height',
+            'bend_radius',
+            'expansion_resolution',
+            'expansion_size',
+            'propagation_resolution',
+        ]
+
+        # Pass all kwargs directly to EMode's settings function
+        kwargs = {key: (value * nm if key in dim_keys else value) for key, value in kwargs.items()}
+        self.settings(**kwargs)
+
+        # Get a list of EMode materials for cleaning GDSFactory material names
+        emode_materials = self.get('materials')
+
+        # Process layer_stack to create EMode shapes
+        max_order = max([info.mesh_order for name, info in layer_stack.layers.items()])
+        min_zmin = min([info.zmin for name, info in layer_stack.layers.items()])
+
+        for layer_name, layer_info in layer_stack.layers.items():
+
+            material = next(
+                (mat for mat in emode_materials if mat.lower() == layer_info.material.lower()),
+                layer_info.material
+            )
+
+            shape_info = {
+                'name': layer_name,
+                'refractive_index': material,
+                'height': layer_info.thickness * nm,
+                'mask': layer_info.width_to_z * nm,
+                'sidewall_angle': layer_info.sidewall_angle,
+                'etch_depth': layer_info.thickness * nm if layer_info.width_to_z > 0 else 0,
+                'position': [0.0, (layer_info.zmin - min_zmin + layer_info.thickness/2) * nm],
+                'priority': max_order - layer_info.mesh_order + 1,
+            }
+
+            # Find a matching CrossSection for this layer
+            xsection_ind = [k for k, s in enumerate(cross_section.sections) if str(layer_info.layer) == str(s.layer) or str(layer_info.derived_layer) == str(s.layer)]
+
+            # Apply settings from the matching CrossSection
+            if len(xsection_ind) > 0:
+                xsection = cross_section.sections[xsection_ind[0]]
+                shape_info['mask'] = xsection.width * nm
+                shape_info['mask_offset'] = xsection.offset * nm
+
+            self.shape(**shape_info)
+
+        return

notebooks/emode.ipynb

@@ -0,0 +1,88 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "id": "dec55ff8",
+   "metadata": {},
+   "source": [
+    "# EMode - Photonic Device Simulation\n",
+    "\n",
+    "The EMode plugin integrates simulation capabilities from [**EMode Photonix**](https://emodephotonix.com) with GDSFactory. This plugin enables the analysis of photonic devices through:\n",
+    "\n",
+    "- Waveguide mode solving using a Finite-Difference Frequency Domain (FDFD) method.\n",
+    "- Propagation simulations using the Eigenmode Expansion (EME) method.\n",
+    "\n",
+    "Cross-sectional simulations are available with a free EMode<sup>2D</sup> license. The propagation module requires an EMode<sup>3D</sup> license.\n",
+    "\n",
+    "See the complete EMode documentation at [**EMode Docs**](https://docs.emodephotonix.com).\n",
+    "\n",
+    "Get an EMode license at the [**EMode Shop**](https://emodephotonix.com/get-emode).\n",
+    "\n",
+    "## Software Requirement\n",
+    "\n",
+    "This plugin requires that the EMode software is already installed on the user's computer. Please refer to the installation guide at [docs.emodephotonix.com/installation](https://docs.emodephotonix.com/installation) for detailed instructions.\n",
+    "\n",
+    "## Using EMode Examples with gplugins\n",
+    "\n",
+    "All of the [**EMode examples**](https://docs.emodephotonix.com/examples) can be adapted for use with the GDSFactory plugin. Simply replace the standard EMode import:"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 7,
+   "id": "f0fbf103",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "import emodeconnection as emc"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "id": "6f832fad",
+   "metadata": {},
+   "source": [
+    "with the plugin-specific import:"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "8b62c1bf",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "import gplugins.emode as emc"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "id": "1f863dfd",
+   "metadata": {},
+   "source": [
+    "The ``gplugins.emode`` import provides the same interface and usage as the ``emodeconnection`` package, detailed in the [EMode Python connection documentation](https://docs.emodephotonix.com/emodeconnection_python)."
+   ]
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Python 3 (ipykernel)",
+   "language": "python",
+   "name": "python3"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 3
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython3",
+   "version": "3.10.8"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 5
+}

pyproject.toml

@@ -72,6 +72,7 @@ sax = ["sax~=0.15.14"]
 schematic = ["bokeh", "ipywidgets", "natsort"]
 tidy3d = ["tidy3d>=2.8.2,<2.9", "gdstk"]
 vlsir = ["vlsir", "vlsirtools"]
+emode = ["emodeconnection"]
 
 [tool.codespell]
 ignore-words-list = 'te, te/tm, te, ba, fpr, fpr_spacing, ro, nd, donot, schem, Ue'