Advanced Electromagnetics

Syllabus

Part I – Interaction between the electromagnetic field and natural materials
Foundations of electromagnetic field theory. Macroscopic response of natural materials. Constitutive relations and material classification. Linearity. Dispersion. Locality. Stationary and homogeneous materials. Causality and Kramers- Kronig relations. Electric response of natural materials. Material polarization. Electronic, atomic/ionic, orientation, interface polarization mechanisms. Lorentz model: derivation and discussion. Drude model: derivation and discussion. Magnetic response of natural materials. Electrodynamic response of a magnetized ferrite. 

Part II – Interaction between the electromagnetic field and artificial materials
Artificial electromagnetic materials. Historical perspective. Chiral materials. Microscopic response of matter. Polarizability concept. Electric polarizability of a dielectric sphere. Magnetic polarizability of a metallic loop. Electric polarizability of a metallic strip. Electric polarizability of a metallic loop. Polarizabilities of the metallic omega particle. Magneto-electric effect. Local field and interaction field. From microscopic to macroscopic response. Homogenization techniques. Maxwell-Garnett formula. Clausius-Mossotti formula. Bruggeman formula. Energy density for dispersive materials. Causality and energy conservation: frequency behavior of the constitutive parameters. Anomalous dispersion. Introduction to metamaterials. Historical overview. Metamaterials and their definitions. Original studies by Victor Veselago. Negative index of refraction. Negative-index materials and their first implementation. Metamaterial terminology. Artificial electric materials with negative permittivity. The wire medium. The parallel-plate medium. Noble metals at optical frequencies. Artificial electric materials in the visible. Epsilon-near-zero metamaterials. Natural and artificial magnetism. The split-ring resonator: concept, analysis, and design. Miniaturization of magnetic particles. The Multiple Split-Ring Resonator: concept, analysis, and design. The Spiral Resonator: concept, analysis, and design. The Labyrinth Resonator: concept, analysis, and design. Modelling of metallic particles in the visible. The kinetic inductance of electrons. The fishnet structure. Route towards negative index material in optics. Optical magnetism. 

Part III – Interaction between the electromagnetic field and living matter
Introduction to bio-electromagnetism. Historical overview and impact. Electric modeling of living tissues. Interaction mechanism, biological/health effects. Physical quantities to determine the risk. Dosimetry and exposure limits. European and national regulation.

Part IV – Electromagnetic invisibility, imaging and sensing (starting from academic year 2019-2020)
Electromagnetic imaging, sensing and cloaking: definitions and basic principles. Microscopy: definition and classification. Optical microscopy basics and principles. Bright field, dark field, phase contract, fluorescence techniques. X-ray and electron microscopy. TEM and SEM. Diffraction limit in optical lenses. The perfect lens: physics, design, implementation and operation. Examples of superlenses working at different frequencies. Hyperbolic metamaterials: definition and properties. The hyperlens: physics, design, implementation and operation. Hybrid super- and hyper-lenses. Near field microscopy. NSOM: basics and principles. NSOM operation modes: illumination, collection, and scattering modes. Scattering and absorption of electromagnetic waves.
Scattering, absorption and extinction cross-sections. Principles of spectroscopy. Rayleigh scattering (elastic response). Raman scattering (inelastic response; Stokes and anti-Stokes scattering). IR spectroscopy. Surface plasmon polariton (SPP): definition and excitation. Electromagnetic sensors based on surface plasmon resonance (SPR): definition, physics, implementation, operation. Angular, wavelength, intensity, phase, polarization modulation of SPR based sensors. SPR based biosensors. Sample preparation. Sensorgrams. Sensitivity, FoM, LoD. Localized Surface Plasmon (LSP): definition and excitation. Electromagnetic sensors based on localized surface plasmon resonance (LSPR): definition, physics, implementation, operation. Principles of Surface Enhanced Raman Spectroscopy (SERS).
Reduction of object observability. Stealth and RAM technologies. Electromagnetic invisibility: definition, and figure of merit. Transformation electromagnetics as a route to invisibility. Alternative approaches to cloaking. Main limitations and assessment. Scattering cancellation approach to cloaking. Volumetric cloaks for cylindrical and spherical objects: analysis and design. Cloaking objects with other shapes. Cloaking a cone. Implementation of scattering cancellation based volumetric cloaks at microwave and optical frequencies. Mantle cloaking: concept, modelling, design, and implementation. Cloaking applications at optical frequencies. Reduction and manipulation of optical forces. Reduction of the Casimir effect. NSOM systems: principles of operation and applications. Transmission mode, reception mode, scattering mode. Partially cloaked NSOM tips for higher resolution images. Cloaking applications in antennas. Cloaking passive objects and obstacles in the near-field of an antenna. Cloaking a receiving antenna. Cloaking transmitting antennas. Non-linear cloaking devices.

Part IV – Guided wave propagation (academic year 2018-2019 only)
Guided propagation of electromagnetic fields. Decomposition of the electromagnetic field in guiding structures. Rectangular, circular, and co-axial waveguides. Parallel-plate waveguides. Microstrip waveguides. Dielectric waveguides. Surface plasmon polaritons. 

Course information

The course comes from the combination of the previous courses Bioelectromagnetics and Microwave Engineering. Because of the origin of the course, Part IV is different in the first year (academic year 2018/2019) to allow the students to grant the whole set of notions required in BS and MS degrees.