Every software package contains a full set of examples suitable for that version and are installed with the software. If you see examples here that are not in your installation you should consider updating to a later version of the software. These examples can be used by beginners and advanced users for product evaluation, teaching purposes, and self-training.
Required Modules
Atlas
- Blaze
- Laser
- Quantum
This example demonstrates the simulation of GaAs/AlGaAs ridge laser diode with multiple longitudinal modes. Previous example showed that TE-like fundamental mode is the main lasing mode. Here we use scalar Helmholtz solver and exclude TM modes, using parameter HELM.TM. Slab transverse modes are neglected. Longitudinal modes are taken into account in the range of energies [1.42; 1.5] eV. To limit the number of longitudinal modes, we set intermode energy separation to 4meV using DELTAE parameter. If this parameter is omitted, energy separation will be that of Fabry-Perot resonator with length set by CAVITY_LENGTH. Laser simulation starts automatically whenever optical gain anywhere in the device becomes positive, which happens just before the threshold. If subthreshold behaviour is of interest, use START parameter on LASER statement.
The key points of this simulation are:
Multi-longitudinal mode simulation, with mode competition
Demonstration of scalar Helmholtz solver
Demonstration of modal spectra.
The results show 2D plots of total optical intensity at anode bias of 1.5V. The IV log file contains information of the power, photon density modal gain, modal loss, and modal refractive index for the fundamental transverse mode. Spectrum log files contain information on gain and spontaneous emission spectra for each quantum well. Modal spectrum log files are stored when SPECTRUM is specified on the SAVE statement with “_modal ” appended at the end of the file name. Modal spectra contain modal gain, modal Rsp, modal photon density and modal lifetime for each longitudinal mode.
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