MATERIALI OTTICI ED OPTOELETTRONICI

Optical and optoelectronic materials have a technological impact in modern life. They include a large selection of materials, developed through an interdisciplinary approach. It can be distinguished two groups of optical materials:  molecular materials and bulk materials which, in turn, can be classified in relation to their application in the optical/optoelectronic field. In this course will be presented and discussed the main families of optical materials, in relation to their optical properties, through the study of their crystal and electronic structure. Particular attention will be devoted to their design, synthesis and characterization, in order to optimize their properties and apply them in optoelectronic devices.

In addition, in the frame of the so-called Dublin Descriptors, this Course helps attain the following cross-disciplinary competences:

• Knowledge and understanding: Students will develop inductive and deductive reasoning. They will acquire knowledge on and understanding of nature and properties of investigated materials and their strict correlation with functional properties.
• Applying knowledge and understanding: Ability to apply the gained knowledge in order to describe optical and optoelectronic phenomena and material functional properties using rigorously the scientific method.
• Making judgements: Developing critical thinking.
• Communication skills: Ability to orally present, using fluent scientific language and appropriate scientific vocabulary, a scientific topic, including any underlying motivations and illustrating any results.

Frontal lessons.

Should teaching be carried out in mixed mode or remotely, it may be necessary to introduce changes with respect to previous statements, in line with the programme planned and outlined in the syllabus.

1. Linear and nonlinear optical properties of materials: Polarizability and linear optical properties of materials. Birefringent crystals. Principles of nonlinear optics. Nonlinear optical processes. Design and techniques for the synthesis of nonlinear optical materials. Electro-optical materials.  Waveguides.

 2. Materials for photonic and optoelectronics: electronic structure in solids. Optical properties. Electro-cathode- and photo-luminescence. High-field electroluminescent materials. Optical properties of semiconductors. Direct and indirect gap materials. p-n junction. Heterojunctions. Composite semiconductor materials ( III-V,  II-VI, etc..): band gap engineering.  Low-field electroluminescent semiconductors materials. LASER. 2,3, and 4 levels LASER. Photovoltaic materials: inorganics, organics, and hybrids. Systems based on the p-n junction: formation of charge carriers, diffusion length, and recombination. Organic and Dye based PV systems. Hybrid PV. PV cell parameters. Preparation techniques of materials. 

3. Optical sensors: Chemical sensors based on absorption, fluorescence, or surface plasmonic resonance: techniques and materials. Application of optical sensors in food safety, and in environmental and biomedical fields. Nanosensors.

 4. Optoelectronic devices: Cathodic ray tubes, High field electroluminescent devices based on powders and thin films. Light emitting diodes. Organic light emitting diodes; Semiconductor Lasers, Ruby, and Nd-YAG lasers. First generation Photovoltaic cells: mono and poly Si-based cells. Thin film cells: CIGS, CdTe, and amorphous Si. New generation cells: DSSC and PSC

1. Riferimenti bibliografici e dispense in lingua inglese
2. Slides delle lezioni in lingua inglese.
3. M. Wakaki, " Optical Materials and Applications", CRC Press, 2013.
4. Y.-L. Chang, "Efficient Organic Light-Emitting Diodes", Pan Stanford Publishing, 2015.
5. J. Singh, “Semiconductor optoelectronics”, Mc Graw Hill, 1995.
6. E. Rosencher and B. Vinter, “Optoelectronics”, Cambridge University Press, 2002.
7. S. Kasap, P. Capper “Handbook of Electronic and photonic Materials” Springer, 2017.

- Second Harmonic Generation: Phase-Matching Condition

- Electro-optic Effect

- Electroluminescence

- Photovoltaic Cells

- Selectivity and Sensitivity of an Optical Chemosensor

- Operation of Organic Light-Emitting Diodes (OLEDs)

- Materials for High-Field Electroluminescent Devices

- Semiconductor Lasers

- Key Parameters of a Photovoltaic Cell

- Types of Electron-Hole Recombinations