ShaneLogic/driftfusion-analysis-plotting

Driftfusion Analysis and Plotting

Access solution structures, calculate physical quantities, and generate visualization plots.

When to Use

• Analyzing completed simulation results
• Calculating currents, quasi-Fermi levels, or recombination rates
• Visualizing spatial or temporal profiles
• Following standard simulation workflows

Solution Structure Access

Access solution structure sol with components:

1. u: 3D matrix [time, space, variable]
2. x: Spatial mesh
3. t: Time mesh
4. par: Parameters object

Variable Order in u:

1. Electrostatic potential
2. Electron density
3. Hole density
4. Cation density (if 1 mobile ionic carrier)
5. Anion density (if 2 mobile ionic carriers)

Output Analysis

Use dfana class to calculate physical quantities:

result = dfana.my_calculation(sol)

Common calculations:

• Currents (electron, hole, total)
• Quasi-Fermi levels
• Recombination rates
• Carrier densities

CRITICAL WARNING: The physical model in Equation Editor is NOT coupled to analysis functions. Users must manually ensure models in dfana and df are consistent.

Plotting

Use dfplot class for visualization:

dfplot.my_plot(sol, optional_arguments)

Variable vs Position

dfplot.n(sol, [t1, t2, ... tm])  % Plot at specific time points

• If time vector omitted, plots final time point

Variable vs Time

dfplot.J(sol, x_position)  % Plot at specific position

Integrated Variables

dfplot.Q(sol, [x1, x2])  % Integrate over spatial range

Generic 2D Plots

dfplot.x2d(sol, 'variable_name')

Standard Simulation Workflow

Example: Cyclic Voltammogram

1. Initialize system:

   init_driftfusion
   

2. Create parameters object:

   par = pci('path/to/Spiro-OMeTAD_perovskite_TiO2.csv')
   

3. Find equilibrium:

   soleq = equilibrate(par)
   

4. Run protocol:

   sol = doCV(soleq.ion, 0, 1.2, -0.2, 0, 50e-3)
   % Parameters: input, V_start, V_max, V_min, V_end, scan_rate
   

5. Plot results:

   dfplot.JVapp(sol, d_midactive)
   

Common Plot Variables

• d_midactive: Position at midpoint of active layer
• n, p: Electron and hole densities
• V: Electrostatic potential
• J: Current density
• Efn, Efp: Quasi-Fermi levels

Output

• Calculated physical quantities (currents, densities, recombination rates)
• Visual plots of simulation data
• Analysis of device performance metrics