The diagnostic output in the Traveling Wave Laser Model (TWLM) allows you to save longitudinal profiles and spectrums of various physical quantities, allowing you to visualize them as needed. A customizable down-sample can be used to down-sample these profiles in time to prevent having to store project files containing extremely large datasets with spatio-temporal variables. This article will detail how the diagnostic outputs are formatted and provide examples with the charge carrier profile.
Diagnostic Quantities
Diagnostic quantities are under the “Diagnostic Properties” category in the element properties table. A table of diagnostic properties can be found in the article on the TWLM element. Further information regarding the theory of the TWLM, which will help you understand intricacies within these physical results can be found in the Knowledge Base article on INTERCONNECT as a Laser Design Platform.
Output Format
All profiles are saved as matrix datasets in the results view. In these multidimensional matrices, each row represents the recorded quantity at each downsampled time step, and the number of rows in the matrix represents the total timesteps divided by the downsample factor. The quantity of each individual row represents different quantities depending on the quantity being recorded:
- For spatial profiles such as charge density, a single row represents the recorded quantity as a function of each discretized segment along the cavity.
- For frequency-dependent quantities such as gain, a single row represents an overall spatio-spectral gain (gain spectrum in each discretized segment).
These profiles can be visualized directly using the visualizer, or can be processed using script commands.
For TWLM with multiple sections, the concatenated profiles will be recorded over the total length of all sections.
The following figures show the carrier density profile and gain spectrum of the TWLM element in the example file carrierProfile.icp. The gain spectrum is plotted for one segment of the TWLM model at 153.75 μm.
See Also
INTERCONNECT as a Laser Design Platform, Laser TW – INTERCONNECT Element