The course aims at learning the tools for the analysis and design of innovative high-tech devices based on the use of artificial electromagnetic materials and metamaterials.
teacher profile teaching materials
Negative-index metamaterials. Classification and terminology. Engheta’s resonator. Pendry’s lens. Transmission-line metamaterials. Miniaturization of electromagnetic components. Miniaturized antennas. Two-dimensional metamaterials: metasurfaces. Design of inclusions for microwave metamaterials. Design of transmission-line metamaterials and design of miniaturized microwave components (elementary cells, phase shifters, rat-race, etc.). Computed-based exercises.
Unit 2: Electromagnetic invisibility and metasurfaces.
Reduction of radar observability. Basic concepts on electromagnetic invisibility. Radar and scattering cross section. Figure of merit for EM cloaks. Basic principles of the transformation of transformation-electromagnetism. Invisibility cloaks based on transformation-electromagnetism. Other approaches to achieve electromagnetic invisibility. Basiuc principles on scattering cancellation. Scattering cancellation by volumetric metamaterials. Scattering cancellation by metasurfaces (mantle cloaking). Mie theory for spherical and cylindrical objects covered by volumetric layers and surface impedances. Implementation of invisibility devices based on the scattering cancellation at microwaves: volumetric materials and metasurfaces. Applications of electromagnetic invisibility to microwaves: invisibility of passive objects, invisibility of receiving antennas and sensors, mutual invisibility of transmitting antennas. Non-linear and waveform-selective electromagnetic invisibility devices and related applications. Computed-based exercises.
Unit 3: Optical metasurfaces.
Optical metasurfaces based on array of nanoparticles. Electromagnetic characterization of metals at optical frequencies. Drude model. Effect of shape and size on the optical response of materials. Surface dispersion effect. Volumetric homogenization techniques of nanoparticle arrays: Maxwell Garnett and Clausius-Mosotti formulas. Two-dimensional homogenization techniques. Applications of optical metasurfaces: electromagnetic invisibility, optical absorbers, anti-reflection coatings and transparent screens. Extension of the two-dimensional model to dielectric metasurfaces. Applications of dielectric metasurfaces. Computed-based exercises.
Module 4: Space-time modulated metamaterials and metasurfaces.
Introduction to EM non-reciprocity based on natural and artificial materials. Introduction to space-time modulated metamaterials. Analysis of a resonator loaded with a space-time modulated metamaterial: coupled mode theory, resonant modes and frequency response. Applications. Free-space and slab propagation in space-time modulated materials. Time-domain propagation in a dielectric slab. Space-time modulated metasurfaces.
Unit 5: Metamaterials for structured fields.
Topological properties of structured fields. Introduction to the concept of orbital angular momentum, phase singularity and topological charge. Generation of EM fields with phase singularities at optical and microwave frequencies. Generation of composite vortices and related topological properties (robustness with respect to the interaction with opaque objects and vortex-less fields). Application examples: patch antenna with Moebius polarization, shaping of the direction pattern, sectorial and saddle radiation patterns. Full-wave and analytical simulations.
Module 6: Measurements of electromagnetic properties of materials.
Techniques for measuring the electromagnetic parameters of materials. Capacitive and inductive method, resonant and non-resonant techniques. Guidelines to choose the appropriate measurement technique. Measuring instruments. Algorithms for parameters retrieval. Nicholson-Ross algorithm.
Programme
Unit 1: Introduction to metamaterials.Negative-index metamaterials. Classification and terminology. Engheta’s resonator. Pendry’s lens. Transmission-line metamaterials. Miniaturization of electromagnetic components. Miniaturized antennas. Two-dimensional metamaterials: metasurfaces. Design of inclusions for microwave metamaterials. Design of transmission-line metamaterials and design of miniaturized microwave components (elementary cells, phase shifters, rat-race, etc.). Computed-based exercises.
Unit 2: Electromagnetic invisibility and metasurfaces.
Reduction of radar observability. Basic concepts on electromagnetic invisibility. Radar and scattering cross section. Figure of merit for EM cloaks. Basic principles of the transformation of transformation-electromagnetism. Invisibility cloaks based on transformation-electromagnetism. Other approaches to achieve electromagnetic invisibility. Basiuc principles on scattering cancellation. Scattering cancellation by volumetric metamaterials. Scattering cancellation by metasurfaces (mantle cloaking). Mie theory for spherical and cylindrical objects covered by volumetric layers and surface impedances. Implementation of invisibility devices based on the scattering cancellation at microwaves: volumetric materials and metasurfaces. Applications of electromagnetic invisibility to microwaves: invisibility of passive objects, invisibility of receiving antennas and sensors, mutual invisibility of transmitting antennas. Non-linear and waveform-selective electromagnetic invisibility devices and related applications. Computed-based exercises.
Unit 3: Optical metasurfaces.
Optical metasurfaces based on array of nanoparticles. Electromagnetic characterization of metals at optical frequencies. Drude model. Effect of shape and size on the optical response of materials. Surface dispersion effect. Volumetric homogenization techniques of nanoparticle arrays: Maxwell Garnett and Clausius-Mosotti formulas. Two-dimensional homogenization techniques. Applications of optical metasurfaces: electromagnetic invisibility, optical absorbers, anti-reflection coatings and transparent screens. Extension of the two-dimensional model to dielectric metasurfaces. Applications of dielectric metasurfaces. Computed-based exercises.
Module 4: Space-time modulated metamaterials and metasurfaces.
Introduction to EM non-reciprocity based on natural and artificial materials. Introduction to space-time modulated metamaterials. Analysis of a resonator loaded with a space-time modulated metamaterial: coupled mode theory, resonant modes and frequency response. Applications. Free-space and slab propagation in space-time modulated materials. Time-domain propagation in a dielectric slab. Space-time modulated metasurfaces.
Unit 5: Metamaterials for structured fields.
Topological properties of structured fields. Introduction to the concept of orbital angular momentum, phase singularity and topological charge. Generation of EM fields with phase singularities at optical and microwave frequencies. Generation of composite vortices and related topological properties (robustness with respect to the interaction with opaque objects and vortex-less fields). Application examples: patch antenna with Moebius polarization, shaping of the direction pattern, sectorial and saddle radiation patterns. Full-wave and analytical simulations.
Module 6: Measurements of electromagnetic properties of materials.
Techniques for measuring the electromagnetic parameters of materials. Capacitive and inductive method, resonant and non-resonant techniques. Guidelines to choose the appropriate measurement technique. Measuring instruments. Algorithms for parameters retrieval. Nicholson-Ross algorithm.
Core Documentation
Learning materials provided by the teacher.Reference Bibliography
To deepen specific topics, students may refer to the following books: Unit 1 N. Engheta, R.W. Ziolkowki, Metamaterials: Physics and Engineering Explorations, Wiley-IEEE Press, 2006. C. Caloz, T. Itoh, Electromagnetic Metamaterials: Transmission Line Theory and Microwave Applications, Wiley-IEEE Press, 2006. C. Simovski, S. Tretyakov, An Introduction to Metamaterials and Nanophotonics, Cambridge University Press, 2020. Unit 2 C.F. Bohren, D.R. Huffman, Absorption and Scattering of Light by Small Particles, Wiley, 1998. E.F. Knott, J.F. Scaeffer, M.T. Tulley, Radar Cross Section, SciTech Publishing, 2004. K. Achouri, C. Caloz, Electromagnetic Metasurfaces: Theory and Applications, Wiley, 2021. Unit 3 S. Tretyakov, Analytical Modeling in Applied Electromagnetics, Artech House, 2003. T.G. Mackay, A. La Lakhtakia, Modern Analytical Electromagnetic Homogenization with Mathematica, IOP Publishing, 2020. Unit 4 R.E. Collin, Antennas and Radiowave Propagation, Mcgraw-Hill College, 1985. C. R. Pollock, M. Lipson, Integrated Photonics, Springer, 2003. Unit 5 D.H. Werner, R. Mittra, Frontiers in Electromagnetics, Wiley-IEEE Press, 2000. Unit 6 Md. Kawsar Alam, Electrical and Electronic Properties of Materials, IntechOpen, 2019.Type of delivery of the course
The course is delivered through theoretical lectures and computed-based exercises.Type of evaluation
The verification of learning consists of an oral test aimed to assess the actual learning level of the concepts and the students' ability to apply them in real contexts.