Chapters authored
Modeling the Bulk and Nanometric Dielectric Functions of Au and Ag
In this work, we model the dielectric functions of gold (Au) and silver (Ag) which are typically used in photonics and plasmonics. The modeling has been performed on Au and Ag in bulk and in nanometric states. The dielectric function is presented as a complex number with a real part and an imaginary part. First, we will model the experimental measurements of the dielectric constant as a function of the pulsation ω by appropriate mathematical functions in an explicit way. In the second part we will highlight the contributions to the dielectric constant value due to intraband and interband electronic transitions. In the last part of this work we model the dielectric constant of these metals in the nanometric state using several complex theoretical models such as the Drude Lorentz theory, the Drude two-point critical model, and the Drude three-point critical model. We shall comment on which model fits the experimental dielectric function best over a range of pulsation.
Part of the book: Magnetic Skyrmions
DFT and TDDFT Calculations of Ground and Excited States of Photoelectron Emission
The Density-Functional Theory (DFT) is a reformulation of the quantum study of a correlated N-body system into a simpler system with independent equations being solved iteratively. The DFT considers only ground states of the systems. The extension to the time-dependent case of this theory is the Time-Dependent Density-Functional Theory (TDDFT) that also takes into account the excited states of the system. These calculations are very interesting in photonics areas. In fact, the interaction between electrons and light in the vicinity of solid surfaces and nanostructures is important as pathway to integrate photonics and electronics. The capability to couple light and electrons in purposefully designed device depends on the capability of creating such devices and the understanding of the underlying science.
Part of the book: Density Functional Theory