Terahertz absorption in GaN epitaxial layers under lateral electric field

3rd International School and Conference on Optoelectronics, Photonics, Engineering and Nanostructures (Saint Petersburg OPEN 2016)

Balagula, R.M.^1 ; Vinnichenko, M. Ya^1 ; Melentev, G.A.^1 ; Moldavskaya, M.D.^1 ; Shalygin, V.A.^1 ; Vorobjev, L.E.^1 ; Firsov, D.A.^1 ; Danilov, S.N.^2 ; Suihkonen, S.^3

Peter the Great St. Petersburg Polytechnic University, St. Petersburg, Russia^1

University of Regensburg, Regensburg

93040, Germany^2

School of Electrical Engineering, Aalto University, Otakaari 1, Espoo, Finland^3

关键词: Absorption cross sections;    Absorption modulation;    Electron concentration;    Free electron absorption;    GaN epitaxial layers;    Lateral electric field;    Polarized perpendicular;    Transport measurements;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/741/1/012147/pdf
DOI  :  10.1088/1742-6596/741/1/012147

来源: IOP

【 摘 要 】

Variation of absorption of terahertz radiation in lateral electric field was investigated in GaN epitaxial layers. Different behaviour of the absorption modulation in electric field was observed for radiation polarized along electric field and perpendicular to it. Joint analysis of optical and transport measurements let us obtain field dependencies of mobility, electron concentration and absorption cross-section. For terahertz radiation polarized perpendicular to the electric field, results are in accordance with Drude model of free electron absorption. Another polarization demonstrates significant deviation that is yet to be studied more thoroughly.