(2.56) |

we get a formal correspondence between relaxation times and mobilities for parabolic bands. If and have the same sign, then is positive.

With this correspondence we get:

One possibility to model is as a function depending on the the local temperature . Hence the equations depend in a nonlinear way on and . Information about the scattering term can be encoded into a fitting ansatz for the mobilities, for example in the form with fitting parameters .

Alternatively, we can approximate the mobilities as functions of temperature and doping using results from bulk Monte Carlo simulations, see Section 2.3.4.

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R. Kosik: Numerical Challenges on the Road to NanoTCAD