The contribution of edge number on the optical properties in ZnO pyramidal quantum dots

Abstract

Considerable advances in the growth process of quantum dots with non-trivial geometries have been obtained. These advances lead to countless applications in quantum optics, quantum information, and biophysics. However, the theoretical investigation of these objects is complex and analytically impossible in most cases. The investigation of pyramidal or conical quantum dots with a comparable height-to-base ratio is one of those problems. That is why the numerical finite element method in the framework of the envelope function approximation has been used to obtain the eigenvalues and eigenfunctions for ZnO pyramidal and conical quantum dots. The mesh domains required for the finite element method calculation were pyramidal domains with bases ranging from an equilateral triangle to an equilateral decagon. Cones were used for the approximation of the mesh objects for pyramidal quantum dots with a larger number of edges. Different head radius to height ratios (½, 1, 2, 3, 4) were considered. The optical transition energies were shown to decrease with the increase in the number of faces. The optical transition strengths were shown to exhibit the opposite behavior. The interband absorption curves generally exhibit a redshift with the increase in the number of edges.

Role of Pyramidal Low-Dimensional Semiconductors in Advancing the Field of Optoelectronics

“…PSQDs possess higher mobilities and longer lifetimes, which would be suited for applications in field-effect transistors and photovoltaic devices requiring fast carrier transport [53]. In addition, PSQDs also have high photoluminescence (PL) efficiency and large specific surface area, which is beneficial to the sensing application [55]. The linear polarization direction of exciton emission is controlled via the direction of the magnetic field in PSQDs with C 3v symmetry so that all-optical multi-qubit gates based on electron spin as a quantum bit could be realized [56,57].…”