Anisotropy Effects on Polar Optical Vibrations in a FreestandingWurtzite Cylindrical Quantum Dot

Abstract

The properties of polar optical phonon vibrations in aquasi-zero- dimensional (Q0D) anisotropic wurtzite cylindrical quantum dot(QD) are analyzed based on the dielectric continuum model and Loudon'suniaxial crystal model. The analytical electrostatic potentials of thephonon vibrations in the systems are deduced and solved exactly. The resultshows that there exist four types of polar mixing optical phonon modes inthe Q0D wurtzite cylindrical QD systems. The dispersive equations andelectron-phonon coupling function for the quasi-confined-half-space (QC-HS)mixing modes are derived and discussed. It is found that once the radius or theheight of the QD approach infinity, the dispersive equations of the QC-HSmixing modes in the Q0D cylindrical QD can naturally reduce to those of theQC and HS modes in Q2D QWs or Q1D QWWs systems. This has been analyzedreasonably from both of physical and mathematical viewpoints.