tidy3d.ModeData#

class tidy3d.ModeData#

Data associated with a ModeMonitor: modal amplitudes and propagation indices.

Parameters
  • monitor (ModeMonitor) – amps : ModeAmpsDataArray Complex-valued amplitudes associated with the mode.

  • n_complex (ModeIndexDataArray) – Complex-valued effective propagation constants associated with the mode.

Example

>>> from tidy3d import ModeSpec
>>> direction = ["+", "-"]
>>> f = [1e14, 2e14, 3e14]
>>> mode_index = np.arange(5)
>>> index_coords = dict(f=f, mode_index=mode_index)
>>> index_data = ModeIndexDataArray((1+1j) * np.random.random((3, 5)), coords=index_coords)
>>> amp_coords = dict(direction=direction, f=f, mode_index=mode_index)
>>> amp_data = ModeAmpsDataArray((1+1j) * np.random.random((2, 3, 5)), coords=amp_coords)
>>> monitor = ModeMonitor(
...    size=(2,0,6),
...    freqs=[2e14, 3e14],
...    mode_spec=ModeSpec(num_modes=5),
...    name='mode',
... )
>>> data = ModeData(monitor=monitor, amps=amp_data, n_complex=index_data)

Show JSON schema
{
   "title": "ModeData",
   "description": "Data associated with a :class:`.ModeMonitor`: modal amplitudes and propagation indices.\n\nParameters\n----------\nmonitor : ModeMonitor\n        amps : ModeAmpsDataArray\n    Complex-valued amplitudes associated with the mode.\nn_complex : ModeIndexDataArray\n    Complex-valued effective propagation constants associated with the mode.\n\nExample\n-------\n>>> from tidy3d import ModeSpec\n>>> direction = [\"+\", \"-\"]\n>>> f = [1e14, 2e14, 3e14]\n>>> mode_index = np.arange(5)\n>>> index_coords = dict(f=f, mode_index=mode_index)\n>>> index_data = ModeIndexDataArray((1+1j) * np.random.random((3, 5)), coords=index_coords)\n>>> amp_coords = dict(direction=direction, f=f, mode_index=mode_index)\n>>> amp_data = ModeAmpsDataArray((1+1j) * np.random.random((2, 3, 5)), coords=amp_coords)\n>>> monitor = ModeMonitor(\n...    size=(2,0,6),\n...    freqs=[2e14, 3e14],\n...    mode_spec=ModeSpec(num_modes=5),\n...    name='mode',\n... )\n>>> data = ModeData(monitor=monitor, amps=amp_data, n_complex=index_data)",
   "type": "object",
   "properties": {
      "monitor": {
         "$ref": "#/definitions/ModeMonitor"
      },
      "type": {
         "title": "Type",
         "default": "ModeData",
         "enum": [
            "ModeData"
         ],
         "type": "string"
      },
      "amps": {
         "title": "DataArray",
         "description": "Complex-valued amplitudes associated with the mode.",
         "type": "xr.DataArray",
         "properties": {
            "__slots__": {
               "title": "__slots__",
               "type": "Tuple[str, ...]"
            }
         },
         "required": [
            "__slots__"
         ]
      },
      "n_complex": {
         "title": "DataArray",
         "description": "Complex-valued effective propagation constants associated with the mode.",
         "type": "xr.DataArray",
         "properties": {
            "__slots__": {
               "title": "__slots__",
               "type": "Tuple[str, ...]"
            }
         },
         "required": [
            "__slots__"
         ]
      }
   },
   "required": [
      "monitor",
      "amps",
      "n_complex"
   ],
   "additionalProperties": false,
   "definitions": {
      "ModeSpec": {
         "title": "ModeSpec",
         "description": "Stores specifications for the mode solver to find an electromagntic mode.\nNote, the planar axes are found by popping the injection axis from {x,y,z}.\nFor example, if injection axis is y, the planar axes are ordered {x,z}.\n\nParameters\n----------\nnum_modes : PositiveInt = 1\n    Number of modes returned by mode solver.\ntarget_neff : Optional[PositiveFloat] = None\n    Guess for effective index of the mode.\nnum_pml : Tuple[NonNegativeInt, NonNegativeInt] = (0, 0)\n    Number of standard pml layers to add in the two tangential axes.\nfilter_pol : Optional[Literal['te', 'tm']] = None\n    The solver always computes the ``num_modes`` modes closest to the given ``target_neff``. If ``filter_pol==None``, they are simply sorted in order of decresing effective index. If a polarization filter is selected, the modes are rearranged such that the first ``n_pol`` modes in the list are the ones with the selected polarization fraction larger than or equal to 0.5, while the next ``num_modes - n_pol`` modes are the ones where it is smaller than 0.5 (i.e. the opposite polarization fraction is larger than 0.5). Within each polarization subset, the modes are still ordered by decreasing effective index. ``te``-fraction is defined as the integrated intensity of the E-field component parallel to the first plane axis, normalized to the total in-plane E-field intensity. Conversely, ``tm``-fraction uses the E field component parallel to the second plane axis.\nangle_theta : float = 0.0\n    [units = rad].  Polar angle of the propagation axis from the injection axis.\nangle_phi : float = 0.0\n    [units = rad].  Azimuth angle of the propagation axis in the plane orthogonal to the injection axis.\nprecision : Literal['single', 'double'] = single\n    The solver will be faster and using less memory under single precision, but more accurate under double precision.\nbend_radius : Optional[float] = None\n    [units = um].  A curvature radius for simulation of waveguide bends. Can be negative, in which case the mode plane center has a smaller value than the curvature center along the tangential axis perpendicular to the bend axis.\nbend_axis : Optional[Literal[0, 1]] = None\n    Index into the two tangential axes defining the normal to the plane in which the bend lies. This must be provided if ``bend_radius`` is not ``None``. For example, for a ring in the global xy-plane, and a mode plane in either the xz or the yz plane, the ``bend_axis`` is always 1 (the global z axis).\n\nExample\n-------\n>>> mode_spec = ModeSpec(num_modes=3, target_neff=1.5)",
         "type": "object",
         "properties": {
            "num_modes": {
               "title": "Number of modes",
               "description": "Number of modes returned by mode solver.",
               "default": 1,
               "exclusiveMinimum": 0,
               "type": "integer"
            },
            "target_neff": {
               "title": "Target effective index",
               "description": "Guess for effective index of the mode.",
               "exclusiveMinimum": 0,
               "type": "number"
            },
            "num_pml": {
               "title": "Number of PML layers",
               "description": "Number of standard pml layers to add in the two tangential axes.",
               "default": [
                  0,
                  0
               ],
               "type": "array",
               "minItems": 2,
               "maxItems": 2,
               "items": [
                  {
                     "type": "integer",
                     "minimum": 0
                  },
                  {
                     "type": "integer",
                     "minimum": 0
                  }
               ]
            },
            "filter_pol": {
               "title": "Polarization filtering",
               "description": "The solver always computes the ``num_modes`` modes closest to the given ``target_neff``. If ``filter_pol==None``, they are simply sorted in order of decresing effective index. If a polarization filter is selected, the modes are rearranged such that the first ``n_pol`` modes in the list are the ones with the selected polarization fraction larger than or equal to 0.5, while the next ``num_modes - n_pol`` modes are the ones where it is smaller than 0.5 (i.e. the opposite polarization fraction is larger than 0.5). Within each polarization subset, the modes are still ordered by decreasing effective index. ``te``-fraction is defined as the integrated intensity of the E-field component parallel to the first plane axis, normalized to the total in-plane E-field intensity. Conversely, ``tm``-fraction uses the E field component parallel to the second plane axis.",
               "enum": [
                  "te",
                  "tm"
               ],
               "type": "string"
            },
            "angle_theta": {
               "title": "Polar Angle",
               "description": "Polar angle of the propagation axis from the injection axis.",
               "default": 0.0,
               "units": "rad",
               "type": "number"
            },
            "angle_phi": {
               "title": "Azimuth Angle",
               "description": "Azimuth angle of the propagation axis in the plane orthogonal to the injection axis.",
               "default": 0.0,
               "units": "rad",
               "type": "number"
            },
            "precision": {
               "title": "single or double precision in mode solver",
               "description": "The solver will be faster and using less memory under single precision, but more accurate under double precision.",
               "default": "single",
               "enum": [
                  "single",
                  "double"
               ],
               "type": "string"
            },
            "bend_radius": {
               "title": "Bend radius",
               "description": "A curvature radius for simulation of waveguide bends. Can be negative, in which case the mode plane center has a smaller value than the curvature center along the tangential axis perpendicular to the bend axis.",
               "units": "um",
               "type": "number"
            },
            "bend_axis": {
               "title": "Bend axis",
               "description": "Index into the two tangential axes defining the normal to the plane in which the bend lies. This must be provided if ``bend_radius`` is not ``None``. For example, for a ring in the global xy-plane, and a mode plane in either the xz or the yz plane, the ``bend_axis`` is always 1 (the global z axis).",
               "enum": [
                  0,
                  1
               ],
               "type": "integer"
            },
            "type": {
               "title": "Type",
               "default": "ModeSpec",
               "enum": [
                  "ModeSpec"
               ],
               "type": "string"
            }
         },
         "additionalProperties": false
      },
      "ModeMonitor": {
         "title": "ModeMonitor",
         "description": ":class:`Monitor` that records amplitudes from modal decomposition of fields on plane.\n\nParameters\n----------\ncenter : Tuple[float, float, float] = (0.0, 0.0, 0.0)\n    [units = um].  Center of object in x, y, and z.\nsize : Tuple[NonNegativeFloat, NonNegativeFloat, NonNegativeFloat]\n    [units = um].  Size in x, y, and z directions.\nname : ConstrainedStrValue\n    Unique name for monitor.\nfreqs : Union[Tuple[float, ...], Array]\n    [units = Hz].  Array or list of frequencies stored by the field monitor.\nmode_spec : ModeSpec\n    Parameters to feed to mode solver which determine modes measured by monitor.\n\nExample\n-------\n>>> mode_spec = ModeSpec(num_modes=3)\n>>> monitor = ModeMonitor(\n...     center=(1,2,3),\n...     size=(2,2,0),\n...     freqs=[200e12, 210e12],\n...     mode_spec=mode_spec,\n...     name='mode_monitor')",
         "type": "object",
         "properties": {
            "type": {
               "title": "Type",
               "default": "ModeMonitor",
               "enum": [
                  "ModeMonitor"
               ],
               "type": "string"
            },
            "center": {
               "title": "Center",
               "description": "Center of object in x, y, and z.",
               "default": [
                  0.0,
                  0.0,
                  0.0
               ],
               "units": "um",
               "type": "array",
               "minItems": 3,
               "maxItems": 3,
               "items": [
                  {
                     "type": "number"
                  },
                  {
                     "type": "number"
                  },
                  {
                     "type": "number"
                  }
               ]
            },
            "size": {
               "title": "Size",
               "description": "Size in x, y, and z directions.",
               "units": "um",
               "type": "array",
               "minItems": 3,
               "maxItems": 3,
               "items": [
                  {
                     "type": "number",
                     "minimum": 0
                  },
                  {
                     "type": "number",
                     "minimum": 0
                  },
                  {
                     "type": "number",
                     "minimum": 0
                  }
               ]
            },
            "name": {
               "title": "Name",
               "description": "Unique name for monitor.",
               "minLength": 1,
               "type": "string"
            },
            "freqs": {
               "title": "Frequencies",
               "description": "Array or list of frequencies stored by the field monitor.",
               "units": "Hz",
               "anyOf": [
                  {
                     "type": "array",
                     "items": {
                        "type": "number"
                     }
                  },
                  {
                     "title": "Array Like",
                     "description": "Accepts sequence (tuple, list, numpy array) and converts to tuple.",
                     "type": "tuple",
                     "properties": {},
                     "required": []
                  }
               ]
            },
            "mode_spec": {
               "title": "Mode Specification",
               "description": "Parameters to feed to mode solver which determine modes measured by monitor.",
               "allOf": [
                  {
                     "$ref": "#/definitions/ModeSpec"
                  }
               ]
            }
         },
         "required": [
            "size",
            "name",
            "freqs",
            "mode_spec"
         ],
         "additionalProperties": false
      }
   }
}

Fields
  • amps (tidy3d.components.data.data_array.ModeAmpsDataArray)

  • monitor (tidy3d.components.monitor.ModeMonitor)

  • n_complex (tidy3d.components.data.data_array.ModeIndexDataArray)

attribute amps: tidy3d.components.data.data_array.ModeAmpsDataArray [Required]#

Complex-valued amplitudes associated with the mode.

Constraints
  • title = DataArray

  • type = xr.DataArray

  • properties = {‘__slots__’: {‘title’: ‘__slots__’, ‘type’: ‘Tuple[str, …]’}}

  • required = [‘__slots__’]

attribute monitor: tidy3d.components.monitor.ModeMonitor [Required]#
attribute n_complex: tidy3d.components.data.data_array.ModeIndexDataArray [Required]#

Complex-valued effective propagation constants associated with the mode.

Constraints
  • title = DataArray

  • type = xr.DataArray

  • properties = {‘__slots__’: {‘title’: ‘__slots__’, ‘type’: ‘Tuple[str, …]’}}

  • required = [‘__slots__’]

normalize(source_spectrum_fn) tidy3d.components.data.monitor_data.ModeData#

Return copy of self after normalization is applied using source spectrum function.

property k_eff#

Imaginary part of the propagation index.

property n_eff#

Real part of the propagation index.