gui.rst

Graphical User Interface Guide

ErwinJr2

The GUI starting program is defined in ErwinJr.py, which includes two tabs: the quantum tab and the optical tab. The quantum tab is mostly a GUI wrapper of :pyQCLayers with a plotting canvas, while the optical tab is for :pyOptStrata

Quantum Tab

A screenshot of the ErwinJr.py quantum tab.

The interface includes 4 columns:

setti	ngBox
Description	Used as a comment, not for calculation
Substrate	Decide substrate, can influence strain and material set
E-field	Global electrical field
Position resolution	Finite-element grid size
Energy resolution	Scan size for the eigen-solver root finder. It only shows when the ODE solver is selected. This should be smaller than the smallest energy difference. If this is too small it's possible to lose some states
No of States Per Period	Determines the number of states to solve for. It only shows when the matrix solver is selected. This should be large enough to cover the range of interest
Repeats	Number of the whole structure
Wavelength	The wavelength is used for optimization and for calculating global gain
Basis Divisions	Defined for basis solver. See :pyQCLayers.solve_basis
Period info	Calculate the total length and doping density

layer	Box
Layer Buttons	Insert above a layer or delete the selected layer
Optimize Buttons	Start optimizing. Optimize Layer only optimize the selected layer on the selected FoM; Global Optimize tries to optimize global gain. The feature is experimental.
Layer Table	Show the table that defines the layer structure

solve	Box
Solve basis button	Call :pyQCLayers.solve_basis and update plot
Solve whole button	Call :pyQCLayers.solve_whole and update plot
Material Table	Define the material used in the structure
Interface Roughness	The interface roughness Δ and Λ See :pyQCLayers.ifr_transition for detail. If Constant IFR is checked, all interfaces are having the same IFR parameters If Constant IFR is not checked, IFR parameters are material dependent The material BEFORE the interface determines the IFR
Plot control	Layer Select: select layer in Layer Table by clicking Zoom: in with the right button of the mouse, out with the left Pan: move with the mouse Reset: make the plot back to the default position and scale Clear: remove all wavefunctions
Calculation box	Pair Select: start to pick states by mouse FoM: calculating full information of the picked state pair Population: calculating the steady state electron population in percentage ->Optics: transport parameters to the Active Core material in the Optical tab Gain Spec: pop a new window showing the gain spectrum

The plot canvas

The black lines (or blue line if a well is selected) are the conduction band bottom of the potential. The states are the colored curve but thick black if selected. Other symmetry points in the band and the plot style of the wavefunctions can be changed from View in the menu bar. States that are thick in line are the selected set of a single period of states. This selected set is used to calculate the electron population distribution. States that are dashed lines are considered not well-bounded.

Export of the figure and data, save and load actions are embedded into File menu; temperature setting and advanced table settings are in Edit menu; options to choose what is included in the plot are listed in View menu.

Optics Tab

A screenshot of the ErwinJr.py quantum tab.

The interface includes 3 columns:

setti	ngBox
Wavelength	Can be transferred from quantum tab but not necessarily the same
Material Block	Defines the customized material. For pure GUI users, it defines Active Core transferred from quantum tab index: the effective refractive index of the material passive loss: the loss that's not defined by gain below Period Length and Periods: Determines the layer width of the Active core
Ridge Geometry	Defines the ridge facet loss for threshold gain calculation Reflectivity depends on the effective refractive index, so the mirror loss will be updated after solved

strat	aBox
The Strata Table	Defines the waveguide structure. At least an Active Core needs to be present. The first and the last layers are environment and substrate that is not meant to be changed
Solving Block	Solve for the first bounded mode and show its character The optimizing is performed for the lowest threshold, restricted to the total width of selected layers in the pop-up window.

The plot canvas

The black line and orange lines are the real and imaginary parts of the refractive index, respectively. The active core can be red based on the selection in View menu.