Molecular Photonics (B-KUL-G9X25A)

3 ECTSEnglish18 First term
POC Chemie


at the level of the total chemistry program:To make sure that the student realizes how molecular materials with advanced optical properties can perform optical functions that are very similar to electronics or can be integrated with electronics and how current research contributes to photonics as an enabling technology in our aging, energy-greedy information society.
 
at the level of this specific course
The student can scale the concept of X-ray diffraction on semiconductor crystals with an electronic bandgap with or without impurity doping, to opalescence of photonic crystals with an optical stopband with or without defect mode passbands. The student can rationalize the effect of a photonic bandgap on the steady-state and time-resolved emission from a photonic crystal.
The student understands the molecular and symmetry aspects needed to impart second- and third-order nonlinear optical properties to a molecular material, both at the single molecule and at the ensemble level, and is able to indicate all engineering steps from the molecule to a working electro-optic modulator device for converting electronic digital data to optical pulses for optical long-distance data transfer.
The student can indicate in a charge-transfer molecule the electron donor and electron acceptor moiety, and relate these to electron transfer and proton transfer properties, and ultimately, to redox and acido-switching of the optical properties.
The student realizes that the molecular requirements for organic photovoltaics and for organic light emitting diodes are very similar and that conjugated materials can contribute to energy saving.
The student realizes that the symmetry requirements for second-harmonic generation and for two-photon fluorescence are different and that these complementary nonlinear optical techniques can be used in diagnostic imaging and photodynamic therapy.
 
at the generic level:
The student can find recent research articles on a given topic, study the specific topic in great depth for himself, and indicate the essentials and present these as course material for his fellow students.

Activities

3 ects. Photonics (B-KUL-G0I15a)

3 ECTSEnglishFormat: Lecture18 First term
POC Chemie

Chapter I
Absorption of light by molecules. Detailed discussion of the factors determining the transition dipole
Excited states in molecular systems: singlets and triplets, localized (Frenkel excitons) and charge transfer states
Energy, bond lengths, acidity and dipole moments of excited states
Excited states in semiconductors (Wannier excitons) (quantum-dots + particle in a box)
 
Chapter II
Fluorescence and phosphorescence
Thermal decay processes of excited states , Fermi Golden Rule
Major experimental techniques of stationary and fast spectroscopy for evaluation of kinetics and spectroscopy of excited states
Generalization of  Woodward Hoffmann rules
 
Chapter III
Formal kinetics of quenching
Quenching by excitation transfer (Förster and Dexter)
Quenching by electron transfer
Quenching by excited state complex formation
Quenching by heavy atoms and paramagnetic effects
 
Chapter IV
Adiabatic electron transfer
Non-adiabatic electron transfer
Solvent reorganization
Distance dependence of electron transfer (superexchange)
Electron transfer to metals and semiconductors
 
Chapter V
Exciton Interaction in Dimers
Exciton Interaction in Large 1- and 2-aggregates
Mixed dimers
Also cfr. content of specific educational activities.

Chapter VI 
Concerted reactions, correlation diagramma, conical intersections, pericyclic minima

Chapter VII
Application of the content of Chapter VI to selected elementary photochemical reactions and related concepts as  biradicals.
 
Chapter VIII
Excitations in semiconductors and metals

*

Photonic atoms, photonic crystals, colloidal photonic crystals, two-dimensional defects in three-dimensional artificial opals.
 
Fluorescence in photonic crystals, bandgap engineering for modulation of the fluorescence and energy transfer.
 
Molecular second- and third-order nonlinear optics, with applications in electro-optic modulation and nonlinear imaging and phototherapy.
 
Principles of organic photovoltaics and organic light emitting diodes.

Evaluation

Evaluation: Molecular Photonics (B-KUL-G2X25a)

Type : Exam during the examination period
Description of evaluation : Oral