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This model can be selected in the configuration file via the parameter `mobility_model = "canali"`.

## CanaliFast Model

The CanaliFast model is an alternative implementation of the Canali model described above. Instead of calculating the powers

$`x^\beta`$ and $`y^{1 / \beta}`$ directly for every requested mobility value, it uses pre-calculated lookup tables with

fixed binning and interpolates between the nearest bins. Depending on the simulation settings, this can provide a speed-up

of more than 30%.

The boundary values and the binning are chosen according to the expected range of the base. For the Canali model, values from

zero up to a field strength of 1000kV/cm are tabulated in 1000 bins. Separate lookup tables are built for the two power

calculations for electrons and holes, respectively.

For the calculation of $`x^\beta`$, the lower boundary is set to 0 since the electric field strength is positive. The upper

boundary is set to the argument of the Canali model formula, i.e. the maximum field strength divided by the

critical field strength provided by the model.

For the calculation of $`y^{1 / \beta}`$, the lower boundary is set to 1 owing to the offset present in the Canali formula.

The upper boundary is again set to the formula argument, i.e. $`1 + (E / E_C)^\beta`$ with $`E`$ being the maximum tabulated

field strength.

For field strengths outside the range, the first and last bin are extrapolated linearly, respectively.

The following plots show a comparison of the mobility and velocity of electrons and holes as calculated from the Canali and

the CanaliFast models. The maximum relative difference occurs at very low electric field strengths and is less than 0.004.

![](./canali_fast_mobility.png)\

*Comparison of the electron and hole mobilities calculated using the Canali and CanaliFast models as a function of the

electric field strength.*

![](./canali_fast_velocity.png)\

*Comparison of the electron and hole velocities calculated using the Canali and CanaliFast models as a function of the

electric field strength.*

## Hamburg Model

The Hamburg model \[[@hamburg]\] presents an empirical parametrization of electron and hole mobility as a function of the