Optical properties of materials

The study of optical properties of materials is a key interdisciplinary field in science and engineering. It is not only a vibrant academic field, but opens the door to innovations of key importance in engineering and industry. This course shall provide an overview of fundamentals and applications and is structured into the following chapters:

1. Interaction of light with matter

This chapter will introduce the Lorentz oscillator model to derive the complex dielectric constant, which is central to understand and simulate optical phenomena. Absorption reflection, transmission, refraction and scattering of light will be treated (Fresnel equations). Particular phenomena such as plasmons, excitons, polaritons will also be discussed. Photoluminescence will be introduced briefly.

2. Optical properties of glasses

Optical transparency, dispersion, temperature dependence of the dielectric function will be treated for different glasses with the aim to understand the propagation of light in fibres for optical fibre communication, nonlinear optics and sensors.

3. Liquid crystals

This important class of materials has given rise to modern display media. Different mesogens and different liquid crystal structures will interact in different ways with polarized light. The most important applications in LCD displays will be discussed.

4. Experimental methods

Some important methods used in the optical characterization of materials will be introduced: Absorption, Fluorescence, specular and diffuse reflection spectroscopy, ellipsometry.

5. Inorganic semiconductors

Absorption and emission in both crystalline and amorphous materials will be studied. Applications in solar cells, photodetectors, LEDs, and lasers will be discussed. Characterization techniques such as electroabsorption as well as time resolved spectroscopy will be treated.

6. Quantum dots

Nanosized objects have impact the optical properties of materials via a confinement effect. Its implication on absorption and fluorescence will be treated. Additionally quantum dots give rise to particular effects such as exciton multiplication. The effect of doping on the optical properties will be treated. Applications in optoelectronics and bioimaging will be discussed.

7. Organic semiconductors

Absorption and emission in organic semiconductors will be treated. The important topic of molecular excitons will be addressed and applications in OLEDs, organic PV, photodetectors and light upconverters will be introduced.