# PLaSK User Manual

#### Page Contents

- DiffusionCyl Class
  - `DiffusionCyl`
  - Methods
  - Attributes
    - Receivers
    - Providers
    - Other
  - Descriptions
    - Method Details
      - `DiffusionCyl.compute()`
      - `DiffusionCyl.compute_overthreshold()`
      - `DiffusionCyl.compute_threshold()`
      - `DiffusionCyl.get_burning_for_mode()`
      - `DiffusionCyl.get_total_burning()`
      - `DiffusionCyl.initialize()`
      - `DiffusionCyl.invalidate()`
    - Receiver Details
      - `DiffusionCyl.inCurrentDensity`
      - `DiffusionCyl.inGain`
      - `DiffusionCyl.inLightE`
      - `DiffusionCyl.inTemperature`
      - `DiffusionCyl.inWavelength`
    - Provider Details
      - `DiffusionCyl.outCarriersConcentration`
    - Attribute Details
      - `DiffusionCyl.algorithm`
      - `DiffusionCyl.geometry`
      - `DiffusionCyl.id`
      - `DiffusionCyl.initialized`
      - `DiffusionCyl.iterative`
      - `DiffusionCyl.maxerr`
      - `DiffusionCyl.mesh`

# DiffusionCyl Class

class electrical.diffusion.DiffusionCyl(name='')

  Calculates carrier pairs concentration in active region using FEM in two-dimensional cylindrical space

## Methods

`compute`([loops, shb, reg]) | Run diffusion calculations
`compute_overthreshold`() | Deprecated method.
`compute_threshold`() | Deprecated method.
`get_burning_for_mode`(mode) | Get power burned over threshold by specified mode [mW].
`get_total_burning`() | Get total power burned over threshold [mW].
`initialize`() | Initialize solver.
`invalidate`() | Set the solver back to uninitialized state.

## Attributes

### Receivers

`inCurrentDensity` | Receiver of the current density required for computations [kA/cm²].
`inGain` | Receiver of the material gain required for computations [1/cm].
`inLightE` | Receiver of the electric field required for computations [V/m].
`inTemperature` | Receiver of the temperature required for computations [K].
`inWavelength` | Receiver of the wavelength required for computations [nm].

### Providers

`outCarriersConcentration` | Provider of the computed carriers concentration [1/cm³].

### Other

`algorithm` | Chosen matrix factorization algorithm
`geometry` | Geometry provided to the solver
`id` | Id of the solver object.
`initialized` | True if the solver has been initialized.
`iterative` | Iterative matrix parameters (see `IterativeParams`)
`maxerr` | Maximum relative residual error (%)
`mesh` | Mesh provided to the solver

## Descriptions

### Method Details

DiffusionCyl.compute(loops=0, shb=False, reg=None)

  Run diffusion calculations

  Parameters:

    - loops (int) – Number of iterations to perform. If 0, the solver will run until the convergence.

    - shb (bool) – If True, the solver will use take into account the spatial hole burning effect.

    - reg (int or None) – Index of the active region to compute. If None, perform computations for all the active regions.

DiffusionCyl.compute_overthreshold()

  Deprecated method. Use compute(shb=True) instead.

DiffusionCyl.compute_threshold()

  Deprecated method. Use compute() instead.

DiffusionCyl.get_burning_for_mode(mode)

  Get power burned over threshold by specified mode [mW].

DiffusionCyl.get_total_burning()

  Get total power burned over threshold [mW].

DiffusionCyl.initialize()

  Initialize solver.

  This method manually initialized the solver and sets `initialized` to True. Normally calling it is not necessary, as each solver automatically initializes itself when needed.

  Returns:

    solver `initialized` state prior to this method call.

  Return type:

    bool

DiffusionCyl.invalidate()

  Set the solver back to uninitialized state.

  This method frees the memory allocated by the solver and sets `initialized` to False.

### Receiver Details

DiffusionCyl.inCurrentDensity = <property object>

  Receiver of the current density required for computations [kA/cm²].

  You will find usage details in the documentation of the receiver class `CurrentDensityReceiverCyl`.

  Example

  Connect the receiver to a provider from some other solver:

      >>> solver.inCurrentDensity = other_solver.outCurrentDensity

  See also

  Receciver class: `plask.flow.CurrentDensityReceiverCyl`

  Provider class: `plask.flow.CurrentDensityProviderCyl`

  Data filter: `plask.filter.CurrentDensityFilterCyl`

DiffusionCyl.inGain = <property object>

  Receiver of the material gain required for computations [1/cm]. It is required only for the SHB computations.

  You will find usage details in the documentation of the receiver class `GainReceiverCyl`.

  Example

  Connect the receiver to a provider from some other solver:

      >>> solver.inGain = other_solver.outGain

  See also

  Receciver class: `plask.flow.GainReceiverCyl`

  Provider class: `plask.flow.GainProviderCyl`

  Data filter: `plask.filter.GainFilterCyl`

DiffusionCyl.inLightE = <property object>

  Receiver of the electric field required for computations [V/m]. It is required only for the SHB computations.

  You will find usage details in the documentation of the receiver class `ModeLightEReceiverCyl`.

  Example

  Connect the receiver to a provider from some other solver:

      >>> solver.inLightE = other_solver.outModeLightE

  See also

  Receciver class: `plask.flow.ModeLightEReceiverCyl`

  Provider class: `plask.flow.ModeLightEProviderCyl`

  Data filter: `plask.filter.ModeLightEFilterCyl`

DiffusionCyl.inTemperature = <property object>

  Receiver of the temperature required for computations [K].

  You will find usage details in the documentation of the receiver class `TemperatureReceiverCyl`.

  Example

  Connect the receiver to a provider from some other solver:

      >>> solver.inTemperature = other_solver.outTemperature

  See also

  Receciver class: `plask.flow.TemperatureReceiverCyl`

  Provider class: `plask.flow.TemperatureProviderCyl`

  Data filter: `plask.filter.TemperatureFilterCyl`

DiffusionCyl.inWavelength = <property object>

  Receiver of the wavelength required for computations [nm]. It is required only for the SHB computations.

  You will find usage details in the documentation of the receiver class `ModeWavelengthReceiver`.

  Example

  Connect the receiver to a provider from some other solver:

      >>> solver.inWavelength = other_solver.outModeWavelength

  See also

  Receciver class: `plask.flow.ModeWavelengthReceiver`

  Provider class: `plask.flow.ModeWavelengthProvider`

  Data filter: `plask.filter.ModeWavelengthFilter`

### Provider Details

DiffusionCyl.outCarriersConcentration(n=0, mesh, interpolation='default') = <property object>

  Provider of the computed carriers concentration [1/cm³].

  Parameters:

    - type (str) – Detailed information which carriers are returned. It can be ‘majority’ to return majority carriers in given material, ‘pairs’ for the concentration of electron-hole pairs, ‘electrons’, or ‘holes’ for particular carriers type.

    - mesh (mesh) – Target mesh to get the field at.

    - interpolation (str) – Requested interpolation method.

  Returns:

    Data with the carriers concentration on the specified mesh [1/cm³].

  You may obtain the number of different values this provider can return by testing its length.

  Example

  Connect the provider to a receiver in some other solver:

      >>> other_solver.inCarriersConcentration = solver.outCarriersConcentration

  Obtain the provided field:

      >>> solver.outCarriersConcentration(0, mesh)
      <plask.Data at 0x1234567>

  Test the number of provided values:

      >>> len(solver.outCarriersConcentration)
      3

  See also

  Provider class: `plask.flow.CarriersConcentrationProviderCyl`

  Receciver class: `plask.flow.CarriersConcentrationReceiverCyl`

### Attribute Details

DiffusionCyl.algorithm = <property object>

  Chosen matrix factorization algorithm

DiffusionCyl.geometry = <property object>

  Geometry provided to the solver

DiffusionCyl.id = <property object>

  Id of the solver object. (read only)

  Example

      >>> mysolver.id
      mysolver:category.type

DiffusionCyl.initialized = <property object>

  True if the solver has been initialized. (read only)

  Solvers usually get initialized at the beginning of the computations. You can clean the initialization state and free the memory by calling the `invalidate()` method.

DiffusionCyl.iterative = <property object>

  Iterative matrix parameters (see `IterativeParams`)

DiffusionCyl.maxerr = <property object>

  Maximum relative residual error (%)

DiffusionCyl.mesh = <property object>

  Mesh provided to the solver