Traveling Wave Laser Model
Keywords
electrical, optical, bidirectional
Ports
Name | Type |
---|---|
input | Electrical Signal |
port 1 | Optical Signal |
port 2 | Optical Signal |
Properties
General Properties
Name | Default value | Default unit | Range |
---|---|---|---|
name Defines the name of the element. |
Laser TW | - | - |
annotate Defines whether or not to display annotations on the schematic editor. |
true | - | [true, false] |
enabled Defines whether or not the element is enabled. |
true | - | [true, false] |
type Defines the element unique type (read only). |
Laser TW | - | - |
description A brief description of the elements functionality. |
Traveling Wave Laser Model | - | - |
prefix Defines the element name prefix. |
TWLM | - | - |
model Defines the element model name. |
- | - | - |
library Defines the element location or source in the library (custom or design kit). |
- | - | - |
local path Defines the local path or working folder $LOCAL for the element. |
- | - | - |
url An optional URL address pointing to the element online help. |
- | - | - |
Standard Properties
Name | Default value | Default unit | Range |
---|---|---|---|
frequency Central frequency of operation. |
193.1 |
THz* *std. unit is Hz |
(0, +∞) |
length Defines the laser active region and cavity length L. |
0.0003 | m | [0, +∞) |
active region width Defines the active region width w. |
5e-006 | m | [0, +∞) |
active region thickness Defines the active region depth d. |
100e-009 | m | [0, +∞) |
current injection efficiency The ratio of total current that gets injected into the quantum wells |
1 | - | [0, 1] |
ambient temperature The ambient temperature. The total laser temperature is the sum of ambient temperature and self-heating temperature increase |
300 | K | [0, +∞) |
current distribution table Defines the current distribution table as distribution weight vs. location. |
<2> [0, 1] | - | - |
load current distribution from file Defines whether or not to load the current distribution from file. |
false | - | [true, false] |
current distribution filename Defines the filename to load the current distribution table. |
current_distribution.dat | - | - |
Waveguide/Mode 1 Properties
Name | Default value | Default unit | Range |
---|---|---|---|
orthogonal identifier 1 The first identifier used to track an orthogonal mode of an optical waveguide. For most waveguide, two orthogonal identifiers '1' and '2' are available (with the default labels 'TE' and 'TM' respectively). |
1 | - | [1, +∞) |
label 1 The label corresponding to the first orthogonal identifier. |
TE | - | - |
polarization 1 Defines the waveguide polarization. |
TE | - | [TE, TM |
loss 1 The loss corresponding to the first orthogonal identifier. |
4342.944819 | dB/m | [0, +∞) |
loss density coefficient 1 The loss density coefficient corresponding to the first orthogonal identifier. When multiplied with carrier density, this can give the free carrier absorption contribution to the total loss. |
0 | dB*m^2 | [0, +∞) |
effective index 1 The effective index corresponding to the first orthogonal identifier. |
3.5 | - | (-∞, +∞) |
group index 1 The group index coefficient corresponding to the first orthogonal identifier. |
4 | - | [0, +∞) |
dispersion 1 The dispersion coefficient corresponding to the first orthogonal identifier. |
0 | s/m/m | (-∞, +∞) |
mode confinement factor 1 Defines the mode confinement factor. |
1 | - | [0, 1] |
spontaneous emission factor 1 Defines the spontaneous emission coupling factor. |
0.01 | - | [0, +∞) |
facet reflectivity left 1 Defines the facet reflectivity left. |
0.9 | - | [0, 1] |
facet phase left 1 Defines the facet phase left. |
0 | rad | (-∞, +∞) |
facet reflectivity right 1 Defines the facet reflectivity right. |
0.9 | - | [0, 1] |
facet phase right 1 Defines the facet phase right. |
0 | rad | (-∞, +∞) |
grating coupling real coefficient 1 Defines the grating coupling real coefficient. |
0 | 1/m | (-∞, +∞) |
grating coupling imag coefficient 1 Defines the grating coupling imag coefficient. |
0 | 1/m | (-∞, +∞) |
Waveguide/Apodization Properties
Name | Default value | Default unit | Range |
---|---|---|---|
apodization function Defines the grating apodization type. |
uniform | - | [uniform, user defined, Gaussian, raised cosine, hyperbolic tangent, sinc |
apodization parameter The grating apodization parameter. |
0.5 | - | (-∞, +∞) |
apodization table Table containing normalized length versus apodization parameters. |
<2,2> [0, 1, 1,...] | - | - |
load apodization from file Defines whether or not to load apodization parameters from an input file or to use the currently stored values. |
false | - | [true, false] |
apodization filename The file containing the normalized length versus apodization parameter values. Refer to the Implementation Details section for the format expected. |
apodization.dat | - | - |
Waveguide/Chirp Properties
Name | Default value | Default unit | Range |
---|---|---|---|
chirp function Defines the grating chirp type. |
none | - | [none, user defined, linear chirp parameter, linear chirp coefficient |
user defined chirp function Defines the user defined grating chirp type. |
chirp coefficient | - | [chirp parameter, chirp coefficient |
chirp parameter The chirp parameter for a linear chirped grating. |
0 | - | (-∞, +∞) |
chirp coefficient The chirp coefficient (dλ/dz) for a linear chirped grating. |
0 | - | (-∞, +∞) |
chirp table Table containing normalized length versus user defined chirp. The user defined chirp type is described in the column header. |
<2,2> [0, 1, 0,...] | - | - |
load chirp from file Defines whether or not to load user defined chirp from an input file or to use the currently stored values. |
false | - | [true, false] |
chirp filename The file containing the normalized length versus the user defined chirp. If the option to select the user defined chirp type exists, the user defined chirp values should correspond to the selected type. If the option to select the user defined chirp type does not exist, the user defined chirp values should correspond to the type described in the column header in the chirp table. Refer to the Implementation Details section for the format expected. |
chirp.dat | - | - |
Waveguide/Recombination Properties
Name | Default value | Default unit | Range |
---|---|---|---|
recombination input parameter Defines whether the input parameter is a table with carried density dependent values or coefficients of a polynomial function. |
coefficients | - | [table, coefficients |
Waveguide/Gain Properties
Name | Default value | Default unit | Range |
---|---|---|---|
gain shape Defines the shape of the gain spectrum. |
Lorentzian | - | [Lorentzian, user defined, Westbrook |
load gain from file Defines whether or not to load measurements from an input file or to use the currently stored values. |
false | - | [true, false] |
gain filename The filename containing the gain spectrum shape fitted data. |
- | - | - |
gain coefficient Defines the gain coefficient a0. |
15e-021 | m^2 | (-∞, +∞) |
carrier density at transparency Defines the carrier density at transparency n0. |
1.5e+024 | m^-3 | (-∞, +∞) |
initial carrier density Defines the initial carrier density. |
1.5e+024 | m^-3 | (-∞, +∞) |
diffusion constant Defines the diffusion constant. |
0 | m^2/s | [0, +∞) |
gain compression factor Defines the gain compression factor, ε. The meaning of this value depends on the chosen gain compression factor type. For more information check the description of the gain compression factor type option. |
0 | m^3 | (-∞, +∞) |
gain compression factor type Defines the type of gain compression factor: material or modal. If the type is material it is a material property of the active layer. The material gain compression factor is usually given in the literature. If the type is modal it must include the mode confinement factor. This can be obtained by multiplying the material gain compression factor with the mode confinement factor. |
material | - | [material, modal |
gain shape center frequency Defines the gain shape center frequency. |
193.1 |
THz* *std. unit is Hz |
(0, +∞) |
gain shape quality factor Defines the gain shape quality factor. |
100 | - | [0, +∞) |
gain shape reference carrier density Defines the gain shape reference carrier density. |
1.5e+024 | m^-3 | [0, +∞) |
differential gain center frequency Defines the differential gain center frequency. |
0 | Hz/m^-3 | (-∞, +∞) |
differential gain quality factor Defines the differential gain quality factor. |
0 | 1/m^-3 | (-∞, +∞) |
Waveguide/Spontaneous Emission Properties
Name | Default value | Default unit | Range |
---|---|---|---|
spontaneous emission from gain Defines whether or not to use the gain shape as the spontaneous emission shape. |
true | - | [true, false] |
load spontaneous emission from file Defines whether or not to load measurements from an input file or to use the currently stored values. |
false | - | [true, false] |
spontaneous emission filename The filename containing the spontaneous emission fitted data. |
- | - | - |
spontaneous emission center frequency Defines the spontaneous emission center frequency. |
193.1 |
THz* *std. unit is Hz |
(0, +∞) |
spontaneous emission quality factor Defines the spontaneous emission quality factor. |
10e-006 | - | [0, +∞) |
spontaneous emission reference carrier density Defines the spontaneous emission reference carrier density. |
1.5e+024 | m^-3 | [0, +∞) |
differential spontaneous emission center frequency Defines the differential spontaneous emission center frequency. |
0 | Hz/m^-3 | (-∞, +∞) |
differential spontaneous emission quality factor Defines the differential spontaneous emission quality factor. |
0 | 1/m^-3 | (-∞, +∞) |
index perturbation Defines the index perturbation type |
linewidth enhancement factor | - | [linewidth enhancement factor, user defined |
linewidth enhancement factor Defines the linewidth enhancement factor α. |
0 | - | (-∞, +∞) |
index perturbation table Defines the index perturbation table |
<2,2> [0, 0, 0,...] | - | - |
load index perturbation from file Defines whether or not to load index perturbation from file |
false | - | [true, false] |
index perturbation filename Defines the filename to load index perturbation table |
index_perturbation.dat | - | - |
Waveguide/Grating Properties
Name | Default value | Default unit | Range |
---|---|---|---|
enable grating Defines whether to add a grating to the device or not. |
false | - | [true, false] |
grating period The grating period. |
0 | m | [0, +∞) |
grating phase slip The grating phase slip. |
1.570796327 | rad | (-∞, +∞) |
grating phase slips table Defines the grating phase slips table |
<2> [0, 0] | - | - |
load phase slips from file Defines whether or not to load phase slips from file |
false | - | [true, false] |
phase slips filename Defines the filename to load phase slips table |
phase_slips.dat | - | - |
Enhanced Properties
Name | Default value | Default unit | Range |
---|---|---|---|
output carrier density Defines whether or not to add an additional output port to monitor the average carrier density. |
false | - | [true, false] |
Numerical Properties
Name | Default value | Default unit | Range |
---|---|---|---|
minimum number of discretized segments Declares user's intent about the minimum number of discretized longitudinal segments. If the calculated number of segments is less than that, a warning will be issued. The actual number of discretized segments is determined by rounding the number of segments in the total length where the segment length is given by the group velocity divided by the sample rate. |
100 | - | (0, +∞) |
convert noise bins Defines if noise bins are incorporated into the signal waveform. |
true | - | [true, false] |
automatic seed Defines whether or not to automatically create an unique seed value for each instance of this element. The seed will be the same for each simulation run. |
true | - | [true, false] |
seed The value of the seed for the random number generator. A value zero recreates an unique seed for each simulation run. |
1 | - | [0, +∞) |
Numerical/Gain Fitting Properties
Name | Default value | Default unit | Range |
---|---|---|---|
gain fitting number of coefficients Defines the maximum number of coefficients for the fitting function. |
5 | - | [0, +∞) |
gain fitting tolerance Defines the mean square error for the fitting function. |
0.05 | - | [0, 1] |
gain fitting maximum number of iterations This determines the maximum number of iterations required before fitting reaches the tolerance error. |
50 | - | [1, +∞) |
gain fitting rolloff Defines the frequency roll off for the fitting function. |
0.05 | - | [0, 1] |
Numerical/Spontaneous Emission Fitting Properties
Name | Default value | Default unit | Range |
---|---|---|---|
spontaneous emission fitting number of coefficients Defines the maximum number of coefficients for the fitting function. |
5 | - | [0, +∞) |
spontaneous emission fitting tolerance Defines the mean square error for the fitting function. |
0.05 | - | [0, 1] |
spontaneous emission fitting maximum number of iterations This determines the maximum number of iterations required before fitting reaches the tolerance error. |
50 | - | [1, +∞) |
spontaneous emission fitting rolloff Defines the frequency roll off for the fitting function. |
0.05 | - | [0, 1] |
Simulation Properties
Name | Default value | Default unit | Range |
---|---|---|---|
output signal mode The output signal mode. |
%output signal mode% | - | [sample, block |
sample rate The sample rate of the generated signal. This is typically set by the global properties in the root (top-most) element. |
%sample rate% | Hz | [0, +∞) |
Diagnostic Properties
Name | Default value | Default unit | Range |
---|---|---|---|
run diagnostic Enables the gain and spontaneous emission spectrum response to be generated as results. |
true | - | [true, false] |
diagnostic size The number of frequency points used when calculating the gain and spontaneous emission spectrum response. |
1024 | - | [2, +∞) |
longitudinal profiles downsample factor
|
1 | - | [1, +∞) |
record carrier density profile Enables carrier density profile output as a function of time and position. |
false | - | [true, false] |
record mode amplitude profile Enables longitudinal mode amplitude profile output as a function of time and position. |
false | - | [true, false] |
record photon density profile Enables longitudinal photon density profile output as a function of time and position. |
false | - | [true, false] |
record gain spectrum profile Enables gain spectrum profile output as a function of time, frequency, and position. |
false | - | [true, false] |
record spontaneous emission spectrum profile Enables spontaneous emission spectrum profile output as a function of time, frequency, and position. |
false | - | [true, false] |
record stimulated emission power density profile Enables stimulated emission power density [W/m^3] profile output as a function of time and position. |
false | - | [true, false] |
record lumped gain spectra Enables lumped gain spectrum output as a function of time and frequency. |
false | - | [true, false] |
record recombination rates profile Enables recombination rates [1/s] profile output as a function of time and position. |
false | - | [true, false] |
record diffusive carrier flux profile Enables diffusion current density profile output as a function of time and position. |
false | - | [true, false] |
record thermionic leakage current Enables thermionic leakage current output as a function of time. |
false | - | [true, false] |
record temperature profile Enables temperature profile output as a function of position and iteration number. |
false | - | [true, false] |
record joule heat power profile Enables Joule heat power profile [W] output as a function of position and iteration number. |
false | - | [true, false] |
record nonradiative recombination heat power profile Enables nonradiative recombination heat power [W] profile output as a function of position and iteration number. |
false | - | [true, false] |
record capture and escape heat power profile Enables capture and escape heat power [W] profile output as a function of position and iteration number. |
false | - | [true, false] |
record absorption heat power profile Enables free carrier absorption heat power [W] profile output as a function of position and iteration number. |
false | - | [true, false] |
Waveguide/Spontaneous Emission/Temperature Properties
Name | Default value | Default unit | Range |
---|---|---|---|
spontaneous emission shape reference temperature Defines the spontaneous emission reference temperature. |
300 | K | [0, +∞) |
spontaneous emission center frequency linear parameter Defines the linear parameter of the temperature dependence of the spontaneous emission center frequency a*T. |
0 | Hz/K | (-∞, +∞) |
spontaneous emission center frequency quadratic parameter Defines the quadratic parameter of the temperature dependence of the spontaneous emission center frequency b*T^2. |
0 | Hz/K^2 | (-∞, +∞) |
spontaneous emission quality factor linear parameter Defines the linear parameter of the temperature dependence of the spontaneous emission quality factor a*T. |
0 | 1/K | (-∞, +∞) |
spontaneous emission quality factor quadratic parameter Defines the quadratic parameter of the temperature dependence of the spontaneous emission quality factor b*T^2. |
0 | 1/K^2 | (-∞, +∞) |
Waveguide/Recombination/Coefficients/Temperature dependence Properties
Name | Default value | Default unit | Range |
---|---|---|---|
radiative recombination eta Defines the radiative recombination temperature coefficient eta 1/lifetime=(Arad+Brad*N+Crad*N^2)*(T/300)^eta. |
0 | - | (-∞, +∞) |
nonradiative linear recombination eta Defines the nonradiative linear recombination temperature coefficient eta Anr*(T/300)^eta. |
0 | - | (-∞, +∞) |
nonradiative quadratic recombination eta Defines the nonradiative quadratic recombination temperature coefficient eta Bnr*(T/300)^eta. |
0 | - | (-∞, +∞) |
nonradiative cubic recombination activation energy Defines the nonradiative cubic recombination temperature activation energy Ea Cnr*exp(-Ea*(1/kT0-1/kT)). |
0 | eV | [0, +∞) |
Waveguide/SCH Properties
Name | Default value | Default unit | Range |
---|---|---|---|
enable SCH To enable separate confinement heterostructure |
false | - | [true, false] |
well carrier capture rate The well carrier capture rate including transport time over the barriers |
14.2857e+009 | 1/s | [0, +∞) |
well carrier escape rate The well carrier escape rate |
7.14286e+009 | 1/s | [0, +∞) |
total well thickness The total well thickness |
10e-009 | m | (0, +∞) |
total barrier thickness The total barrier thickness |
10e-009 | m | (0, +∞) |
Waveguide/Surface Recombination Properties
Name | Default value | Default unit | Range |
---|---|---|---|
left facet surface recombination velocity Defines the left facet surface recombination velocity. |
0 | m/s | [0, +∞) |
right facet surface recombination velocity Defines the right facet surface recombination velocity. |
0 | m/s | [0, +∞) |
Waveguide/Recombination/Coefficients Properties
Name | Default value | Default unit | Range |
---|---|---|---|
radiative linear recombination coefficient Defines the radiative linear recombination coefficient Arad. |
250e+006 | 1/s | (-∞, +∞) |
radiative quadratic recombination coefficient Defines the radiative quadratic recombination coefficient Brad. |
0 | m^3/s | (-∞, +∞) |
radiative cubic recombination coefficient Defines the radiative cubic recombination coefficient Crad. |
0 | m^6/s | (-∞, +∞) |
nonradiative linear recombination coefficient Defines the nonradiative linear recombination coefficient Anr. |
0 | 1/s | (-∞, +∞) |
nonradiative quadratic recombination coefficient Defines the nonradiative quadratic recombination coefficient Bnr. |
0 | m^3/s | (-∞, +∞) |
nonradiative cubic recombination coefficient Defines the nonradiative cubic recombination coefficient Cnr. |
0 | m^6/s | (-∞, +∞) |
Waveguide/Mode 1/Temperature dependence Properties
Name | Default value | Default unit | Range |
---|---|---|---|
temperature index perturbation Defines the temperature index perturbation type |
linear | - | [linear, user defined |
temperature index perturbation linear coefficient Defines the temperature index perturbation linear coefficient dn/dT. The reference temperature is 300 K. |
0 | 1/K | (-∞, +∞) |
temperature index perturbation table Defines the temperature index perturbation table |
<2,2> [0, 0, 0,...] | - | - |
load temperature index perturbation from file Defines whether or not to load temperature index perturbation from file |
false | - | [true, false] |
temperature index perturbation filename Defines the filename to load temperature index perturbation table |
index_perturbation_temperature.dat | - | - |
Waveguide/SCH/Thermionic leakage Properties
Name | Default value | Default unit | Range |
---|---|---|---|
thermionic leakage model Defines the type of thermionic leakage model. |
none | - | [none, Schneider1988 |
quantum barrier height Defines the quantum energy barrier height. |
0.1 | eV | [0, +∞) |
SCH barrier height Defines the separate confinement heterostructure energy barrier height. |
0.2 | eV | [0, +∞) |
quantum well effective mass Defines the quantum well effective mass. |
0.05 | me | [0, +∞) |
quantum barrier effective mass Defines the quantum barrier effective mass. |
0.1 | me | [0, +∞) |
Waveguide/Recombination/Table Properties
Name | Default value | Default unit | Range |
---|---|---|---|
load recombination from file Defines whether or not to load recombination data from an input file or to use the currently stored values. |
false | - | [true, false] |
recombination filename The file containing the recombination data. Refer to the Implementation Details section for the format expected. |
- | - | - |
recombination table A matrix editor for users to read the element recombination data values. |
<3> [0, 0, 0] | - | - |
Waveguide/Gain/Temperature Properties
Name | Default value | Default unit | Range |
---|---|---|---|
gain shape reference temperature Defines the gain shape reference temperature. |
300 | K | [0, +∞) |
gain coefficient linear parameter Defines the linear parameter of the temperature dependence of the gain coefficient a*T. |
0 | m^2/K | (-∞, +∞) |
gain coefficient quadratic parameter Defines the linear parameter of the temperature dependence of the gain coefficient a*T. |
0 | m^2/K^2 | (-∞, +∞) |
transparency density linear parameter Defines the linear parameter of the temperature dependence of the carrier density at transparency a*T. |
0 | 1/m^3/K | (-∞, +∞) |
transparency density quadratic parameter Defines the quadratic parameter of the temperature dependence of the carrier density at transparency b*T^2. |
0 | 1/m^3/K^2 | (-∞, +∞) |
center frequency linear parameter Defines the linear parameter of the temperature dependence of the gain shape center frequency a*T. |
0 | Hz/K | (-∞, +∞) |
center frequency quadratic parameter Defines the quadratic parameter of the temperature dependence of the gain shape center frequency b*T^2. |
0 | Hz/K^2 | (-∞, +∞) |
quality factor linear parameter Defines the linear parameter of the temperature dependence of the gain shape quality factor a*T. |
0 | 1/K | (-∞, +∞) |
quality factor quadratic parameter Defines the quadratic parameter of the temperature dependence of the gain shape quality factor b*T^2. |
0 | 1/K^2 | (-∞, +∞) |
Waveguide/Self-heating Properties
Name | Default value | Default unit | Range |
---|---|---|---|
enable self-heating Enables self-heating model. |
false | - | [true, false] |
active layer thermal resistivity Defines the active layer thermal resistivity |
100e-012 | m*K/W | [1e-10, +∞) |
active-layer-to-ambient thermal resistance Defines the active-layer-to-ambient thermal resistance. |
100e-012 | K/W | [1e-10, +∞) |
effective electrical resistance Defines the effective electrical resistance folded onto the active layer. If the actual resistive layer is not close to the active layer scale it appropriately to have the same effect on the active layer temperature. |
0 | Ohm | [0, +∞) |
active layer band gap Defines the active layer band gap. |
0 | eV | [0, +∞) |
Multisection Laser Properties
Name | Default value | Default unit | Range |
---|---|---|---|
multisection definition This struct allows the definition of input properties for multisection lasers, where each section may have a different property value. Each field in the struct must correspond to one of the supported TWLM properties by name and type. The data size of each struct field represents the number of laser sections and it must be equal for all fields in the struct. |
- | - | - |
====================================
Implementation Details
For more information regarding the implementation of the TWLM laser and how to set various parameters in the element, see the Knowledge Base Article INTERCONNECT as a Laser Design Platform.
TWLM Application Gallery Examples
- Multi-Quantum Well (MQW) Edge Emitting Laser
- Self-heating in AlGaInAs-InP multi-quantum well (MQW) laser
- Fabry-Perot laser using travelling wave laser model (TWLM)
- DFB laser using travelling wave laser model (TWLM)
- DBR laser using travelling wave laser model (TWLM)
- Laser with an external microring resonator and sub-MHz linewidth
- Multisection DFB laser with partially corrugated gratings
- Gain fitting for travelling wave laser model (TWLM)