Abstract
By comparison of calculated imaginary parts of the ordinary and extraordinary dielectric functions of wurtzite semiconductors near the band gap with experimental results, we demonstrate that the interband matrix elements ${E}_{P}^{\ensuremath{\parallel}}$ and ${E}_{P}^{\ensuremath{\perp}}$ of the momentum operator parallel and perpendicular to the optic axis are different. ${E}_{P}^{\ensuremath{\parallel}}$ exceeds ${E}_{P}^{\ensuremath{\perp}}$ and their ratio increases along the series CdSe, CdS, ZnO. The $u$ parameters of GaN, InN, and AlN suggest that the ${E}_{P}^{\ensuremath{\parallel}}/{E}_{P}^{\ensuremath{\perp}}$ ratio should increase along this series as well. We also determined the conduction-band dispersion relation and nonparabolicity, as well as the effective mass, as a function of electron concentration and wave vector for GaN, ZnO, CdS, and CdSe. In addition, optical response due to transitions into exciton-phonon complexes was observed and analyzed. We conclude that up to about ten phonons may participate in such absorption processes in ZnO.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
