some theory backgroud of photocurrent about the indirect gap semiconductor

[njuxyh]

Dear:
i have a question about the photocurrent model in quantumATK.
If there is an indirect gap semiconductor, its direct gap is A, and indirect gap B , of course, A is bigger than B, so it is an indirect band gap .
so i am wondering in the theoretical framework of quantumATK, the allowed smallest transition energy of an electron from valence to conductance is A or B? i.e the indirect inter-band transition is allowed? because it needs phonon energy because momentum difference .


 

[Daniele Stradi]

Hello,

Inelastic transition can be also considered by means of the special thermal displacement method, which we have used to calculate the photocurrent in a silicon p-n junction, see:
https://journals.aps.org/prapplied/abstract/10.1103/PhysRevApplied.10.014026

Best,
Daniele