Contribution of Semi-Quantum Dielectric Function Models to the Analysis of Infrared Spectra

Abstract

A new approach to modeling using semi-quantum dielectric function models is proposed for the retrieval of the optical functions from infrared spectra. The powerful points of the method are shown throughout the analysis of two semitransparent materials, MgO and KBr. All the results are discussed in light of those obtained with classical techniques. This type of model is able to retrieve, for example, the extinction index in a range that covers at least six orders of magnitude and gives access to highly valuable information about high-order phonon processes.

Effects of Au layer thickness and number of bilayers on the properties of Au/ZnO multilayers

“…Similar growth was found on other substrates, sapphire (11)(12)(13)(14)(15)(16)(17)(18)(19)(20), silica glass and lime glass. 40 The displacement of the Bragg peak toward lower angle was already observed in sputtered ZnO films of similar thickness prepared under different conditions, as well as in Zn 0.95 Mn 0.05 O films.…”

“…In order to extract structural information, reflectance spectra were fitted using the FOCUS code. 16 X-ray diffraction (XRD) was carried out in a standard laboratory diffractometer (Bruker D8 TT) by using the K a radiation line of Cu in the h-2h configuration.…”

“…The dielectric function for pure ZnO and for as-prepared ZnO[Au (1.8) /ZnO] 75 , is written as the sum of a constant contribution due to bound electrons, e 1 , and Gaussian components which take into account the absorption of distributions of vibrational modes occurring in disordered materials. 16,23 Each absorption band j is characterized by three parameters, A j , x j , and r j , which represent respectively the amplitude, the peak position and the full width at half maximum. The fitting procedure also needs to introduce the film thickness, d, and substrate thickness.…”

Texture and Porosity Effects on the Thermal Radiative Behavior of Alumina Ceramics

“…[1][2]). The optical and radiative properties of single crystals and non porous materials are relatively well-known and completely defined by the only knowledge of intrinsic parameters such as the complex refractive index and the thickness of the material [3][4][5]. Nevertheless, these properties are modified by extrinsic parameters in the case of porous materials such as ceramics.…”

Modification of the properties of TiN thin structures onsilicon substrate by ion bombardement

“…Za fitovanje IR krivi reflektance korišćen je kompjuterski program FOCUS [94]. Otvoreni kvadrati se odnose na optičku otpornost koja je kod implantiranih uzoraka izračunata za oštećeni region TiN sloja (leva skala), dok se puni krugovi odnose na električnu otpornost modifikovanih slojeva (desna skala).…”