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Published on: January 19, 2018
Dopant-Induced Electric Fields and Their Influence on the Band-Edge Absorption of GaN
1Department of Physics, and Shenzhen Institute of Research and Innovation (HKU-SIRI), The University of Hong Kong, Pokfulam Road, Hong Kong, China.
Abstract:
Dopant-induced local electric fields and their influence on the band-edge absorption of GaN are theoretically examined. For dopant-induced electric field distribution, it is derived with Bayes' rule. For the average electric field strength, it is revealed to be quite strong, i.e., in an order of 104 V/cm in GaN with a fairly low dopant density. On the basis of the Franz-Keldysh mechanism, influence of the dopant-induced electric fields on the band-edge absorption coefficient of GaN is then investigated. Without any adjustable parameters, absorption coefficients of GaN are computed and in good agreement with the available experimental values.
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