The material properties within these databases allow for a complete closed loop design of a laser, starting with the nominal structural design (layer-widths, -compositions and dopant concentrations) and predicting the operating characteristics from lasing wavelength to input-output characteristics within the error of the experiment.
Our quantitative calculations predict essential material characteristics for a wide variety of optoelectronic devices including semiconductor lasers, amplifiers or modulators. The analysis is rather general requiring very few restrictions to the material systems or structural layouts.
Using state of the art microscopic many-body calculations we calculate:
• gain, absorption, and refractive index spectra,
• spontaneous emission (photo luminescence) spectra,
• loss currents due to radiative recombination,
• loss currents due to Auger processes,
• intraband (free carrier) absorption,
As well as related quantities such as differential gain or linewidth enhancement factors.
Our approach includes microscopic calculations of dephasing times and line shape functions, thus avoiding phenomenological inputs needed in less sophisticated approaches.
In a variety of comparisons with experimental measurements the results of our calculations have been shown to be accurate to within the experimental error. All significant features, such as gain amplitudes, line shapes, spectral positions or recombination currents and their dependencies on the carrier density/pump current or temperature are reproduced correctly, demonstrating the predictive capabilities of our simulations.
as correct input for simulators calculating device performance and characteristics like the RSoft design tools from Synopsys Inc., or Crosslight Software Inc.'s Lastip,
to help speed up and reduce expenses occurring in the development of new devices (see e.g. the example description),
for precise device analysis as explained for the examples of an edge-emitting device and a VECSEL in the example description.
All Gain Table calculations are based on state of the art fully microscopic many-body models.
The only input these models require are the nominal structural design (layer width, material compositions and possible doping concentrations) and well-known basic material parameters that can be found in the standard literature, like bulk bandstructure parameters (Luttinger parameters, strain constants and bandgaps), lattice constants, phonon coupling constants, background refractive indices, dielectric constants and band-offsets.
They do not require or allow any phenomenological fit parameters like line broadenings, dephasing times or radiative- or Auger-recombination constants. They have been tested for various materials and device configuration to yield quantitatively correct results within the scattering of the experiment (see the examples). Thus, they are truly predictive.
For all calculations we use fully coupled 8×8 KP-bandstructure models (see Refs.[10], [31]). For dillute Nitrides this is coupled to an anti-crossing model for the conduction bands (see Ref.[8]).
If internal electric fields due to piezoelectric effects or ionized dopants or external electric fields due to applied Voltages are present, the screening of these fields by charge inhomogenities is included by coupling the bandstructure calculation self consistently to a Poisson solver.
Although not required by the models, Gain Tables generally assume that the carriers are in thermal equilibrium and can be described by Fermi distribution. Non-equilibrium effects like carrier relaxation and spectral hole burning and their influence on spectral properties can be investigated in a consulting type environment.
Details about the theoretical models can be found in the SimuLase manual and our various publications.
The typical use of SimuLase™ and data created by it is described for the examples of an edge emitting device and a VECSEL in the examples guide.
