# Graphical User Interface Guide¶

The GUI starting program is defined in ErwinJr.pyw. The software can be start by python ErwinJr.pyw [filename]. It’s mostly a GUI wrapper of QCLayers with a plotting canvas.

A screenshot of the ErwinJr.pyw GUI.

The interface includes 4 columns:

settingBox

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 eigen solve root finder. This should be smaller than smallest energy difference. If this is too small it’s possible to lose some states

Repeats

Number of the whole structure

Basis Divisions

Defined for basis solver. See QCLayers.solve_basis()

Period info

Calculate total length, doping density and sheet density

layerBox

Layer Buttons

insert above layer and delete selected layer

Layer Table

Show the table that defines the layer structure

solveBox

Solve basis button

Call QCLayers.solve_basis() and update plot

Solve whole button

Call QCLayers.solve_whole() and update plot

Material Table

Define the material used in the structure and give some information about the material

Plot control

• Layer Select: select layer in Layer Table by clicking

• Zoom: in with right button of mouse, out with left

• Pan: move with mouse

• Reset: make the plot back to default position

• Clear: remove all wavefunctions

Calculatin box

• Pair Select: start to pick states by mouse

• FoM: calculating full information of the picked state pair

• Filter: remove unbounded state smartly (to improve)

And a plotting canvas.

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 is listed in View menu.

Todo

desktop shortcut and register to system