PHOTONIC DEVICES

Teachers: 
POLI Federica
CANDIANI Alessandro
Credits: 
9
Site: 
PARMA
Year of erogation: 
2021/2022
Unit Coordinator: 
Disciplinary Sector: 
Electromagnetic Fields
Semester: 
Second semester
Year of study: 
2
Language of instruction: 

English

Learning outcomes of the course unit

At the end of the course the students will gain knowledge on light propagation in waveguides and optical fibers, and on the working principles of the main photonic components used in communication systems (lasers, modulators, couplers, amplifiers). Moreover, the students will be able to:
− analyze and describe a communication system based on optical fibers;
− analyze the properties of waveguides and optical fibers, and of the main photonic devices with simulations based on a numerical method;
− summarize and describe the main results of a numerical analysis, using a proper technical vocabulary;
− understand the technical specifications of optical fibers and photonic components, in order to properly use them in a laboratory setup;
− summarize and describe the main results of an experimental activity in laboratory.

Course contents summary

The course provides the theoretical bases to study light propagation in waveguides and optical fibers, and the working principles of photonic devices used in communication systems. Conventional optical fibers are thoroughly described, with particular emphasis on the characteristics that make them suitable for optical communications. The main optical components and photonic devices used in modern communication systems, such as lasers, modulators, couplers and amplifiers, are presented in detail. Special attention is paid to the main research topics in the field of photonics for optical communications.
Some lessons of the course will be devoted to experimental activities in laboratory and to numerical simulations.

Course contents

Each class corresponds to 2 hours
CLASS 1: Introduction to modern photonic technologies
CLASS 2: Dielectric slab waveguide
CLASS 3: Main properties and light guiding mechanism of conventional optical fibers
CLASS 4: Guided modes in step-index fibers
CLASS 5: Guided mode dispersion curve, single-mode and multi-mode regime
CLASS 6: Weakly guiding approximation and pseudo-modes LP
CLASS 7: Attenuation mechanisms of conventional optical fibers
CLASS 8: Chromatic dispersion in optical fibers
CLASS 9: Optical fibers with specific dispersion properties (DSFs, NZDSFs, DCFs)
CLASS 10: Optical fibers for submarine communications
CLASS 11: Optical fibers for Space Division Multiplexing (SDM)
CLASS 12: Hollow-core photonic crystal fibers for optical communications
CLASS 13: Laser working principle and different laser types
CLASS 14: Semiconductor lasers
CLASS 15: Optical amplfication mechanisms
CLASS 16: Doped fiber amplifiers
CLASS 17: Photodetection process
CLASS 18: Photodiodes
CLASS 19: Couplers
CLASS 20: Optical modulators
CLASS 21: Elements of photonic integrated circuits
CLASS 22: Elements of silicon photonics

Numerical simulation activities:
CLASS 1: Introduction to numerical simulations of optical fibers and photonic devices
CLASS 2: Calculation of the guided modes in a dielectric slab waveguide
CLASS 3: Calculation of the guided modes in a step-index fiber
CLASS 4: Calculation of the chromatic dispersion of the guided modes in an optical fiber
CLASS 5: Numerical analysis of the properties of specialty optical fibers
CLASS 6: Numerical analysis of a directional coupler
CLASS 7: Numerical analysis of a Mach-Zender modulator
CLASS 8: Numerical analysis of the properties of silicon waveguides

Experimental activities in laboratory:
CLASS 1: Introduction to laboratory activities: instuments and good practice
CLASS 2: Optical workbench: design and implementation of an experimental setup
CLASS 3: Optical fibers: fiber splicing (fiber end cut, splice, connectors) and spectral characterization (attenuation and dispersion)
CLASS 4: Active components: laser and diode sources, coupling to optical fibers
CLASS 5: Passive components: couplers, modulators and gratings, coupling to optical fibers
CLASS 6: Realization of an optical system, performance evaluation

Recommended readings

S. Selleri, L. Vincetti, A. Cucinotta, “Optical and Photonic Components”, Esculapio, 2015
B. E. A. Saleh, M. C. Teich, “Fundamentals of Photonics”, 3 rd Edition, Wiley, 2019
Scientific papers suggested during the lessons of the course.

Teaching methods

The teaching activities include lessons carried out using multimedia presentations, videos/images and web pages (44 hours). In addition, practice lessons are planned, with experimental activities in laboratory (12 hours) and numerical simulations carried out using a software for the analysis of the electromagnetic wave propagation at optical frequencies in linear and non-linear optical media (16 hours).
The slides of the presentations shown during the lessons are uploaded to the Elly web site of the course. The registration to the course is necessary to download the slides. Please notice that the presentations are considered an essential part of the teaching material.
Students who are not attending to the course should periodically check the teaching material and the information provided by the instructor on the Elly web site.
It should be noted that the teaching methods may be subject to change according to the actual health situation.
Further information about the lessons will be provided just before the beginning of the course.

Assessment methods and criteria

The learning assessment is made with:
− an oral exam with questions on the topics developed during the
lectures, with the aim to verify the learning level of the student. The oral
exam is evaluated in the range 0/30;
− an individual report on a numerical simulation activity carried on with
the software used during the practice lessons. This individual activity concerns one of the kind of photonic devices or optical fibers presented during the laboratory lessons. Students can collect the text describing the activity during the last lesson of the course, or later by appointment with the professor. A Word template in .docx is available on the Elly web-site of the course. Students are encouraged to use it to prepare the report. The .pdf file of the report must be sent by email to the professor no later than three days before the date of the oral exam. The report is
evaluated according to accuracy, completeness and clarity, in the range 0/30.
The mark of the oral exam is communicated to the student at the end of the oral test. The mark of the report is announced to the student just after the end of the oral exam. At the same time, the student can view the report with the corrections. The final mark is calculated as the average of the ones obtained for the oral exam and the report, which are both in the range 0/30. The honors are given to the students who obtain the maximum score for both the oral exam and the report.
The online registration to the exam is mandatory and it is possible until three days before the exam date.
If, due to the health situation, it will be necessary to do online exams, the oral exam will be online using Teams. The oral exam will be the same as the one done in presence. Students are invited to read carefully all the guides available in the section “Oral exam” of the web-site http://selma.unipr.it/ before participating to the online exams.
Further information about the examination procedure will be given to the students during the lessons and made available on the Elly web-site of the course.
It should be noted that the learning assessment methods may be subject to change according to the actual health situation.