(2.224) | ||

(2.225) |

with

(2.226) |

where an energy independent carrier lifetime has been assumed and the approximation (2.213) has been used. Since the subsequent integration is carried out in -space rather than in the energy domain, the effective density of states does not appear ( ) due to the normalization of the distribution function, .

Using eqns. (2.93) to (2.95) together with eqn. (2.225) yields

Eqn. (2.228) is written as a net power generation rate

(2.230) |

The index must be used since in contrast to the net recombination rate the net energy generation rate is different for both carrier types.

The contribution to the moment equations of odd order can be neglected since the right hand
sides of eqns. (2.76) to (2.78) are several
orders of magnitude larger than the additional generation term^{2.13}.

Rewriting eqn. (2.228) leads to

(2.231) | ||

(2.232) |

Eqn. (2.229) can be manipulated in the same way, so the even moments read

(2.233) | ||||

(2.234) | ||||

(2.235) |

The interpretation of eqn. (2.234) is that a recombining electron on average removes the energy from the system, while a generated electron introduces an energy of only , which means that generated electrons are initially cold.