Indirect Interband Transition
- Practical Electron Microscopy and Database -
- An Online Book -  




The electronic and optical interband transitions are categorized by direct and indirect transitions because the conduction band bottom and the valance band top contain more than one extrema. The electronic and optical band gaps can be calculated by the predominant mechanism of band to band transitions and are normally less than several volts. In the indirect transition, the electrons transit from the valence band top to the conduction band bottom with participation of photons and appropriate phonons. In this case, the absorption coefficient can be given by [1],

       electronic and optical interband transitions ------------------------------ [3950]

       B -- A constant
       Egi -- The indirect energy gap
       Ep -- The energy of the absorbed (+) or emitted (-) phonons.














[1] El-Korashy A, El-Fadl AA (1999) Phys B 271:205.