GaAs/AlGaAs Stripe Geometry Laser

laserex03.in : GaAs/AlGaAs Stripe Geometry Laser

Requires: Blaze/Laser
Minimum Versions: Atlas 5.28.1.R

This example demonstrates simulation of a the stripe geometry GaAs/AlGaAs laser diode. Physically based frequency dependent optical gain model is used in this example. The example shows:

  • Laser structure definition using Atlas syntax
  • Material parameters specification
  • Setting conventional physical models
  • Device initial biasing
  • Activating LASER module of Atlas
  • Mesh definition for solving the Helmholtz wave equation
  • Definition of laser physical models and their parameters including optical gain model
  • Calculation of laser electrical and optical characteristics

In this example the same approach is applied to simulate a laser structure of a different geometry and material composition. The active region of the device under consideration represents a narrow stripe made of GaAs included between two AlGaAs regions. The logistics of the structure, material parameters and physical models definition repeat that of the previous two examples in this section. Refer to those examples for more detailed explanations.

After performing the LASER simulation and saving the results in the log and structure output files, the following results are displayed in TonyPlot:

  • Total light output power versus current
  • Light intensity distribution over the structure

Since stripe geometry lasers do not provide sufficient light confinement in the direction parallel to the p-n- and heterojunction planes, the lasing region can be smeared laterally along the active region or shifted to a side of the structure due to fluctuations in the carrier density and dielectric permittivity. The latter may lead to the spatial hole burning effect and have a negative influence on the laser characteristics. In this particular example spatial hole burning does not occur, but the lack of index waveguiding in the lateral direction which results in spreading the lasing area along the active region is clearly visible.

To load and run this example, select the Load button in DeckBuild > Examples. This will copy the input file and any support files to your current working directory. Select the Run button in DeckBuild to execute the example.