EE 30358 Electromagnetic Fields and Waves II

1. EE 30358 Electromagnetic Fields and Waves II • Instructor: Arpad I. CSURGAY • 268 Fitzpatrick Hall • acsurgay@nd.edu TA: Timothy VASSEN • Textbook: Magdy F. Iskander • Electromagnetic Fields and Waves • Chapters 5 to 9: Electromagnetic Waves Lectures : Tuesday/Thursday 11:00 -12:15 DeBartolo 129 Problems: roughly weekly Grading: 30% problems; 30% midterm; 40% final Dr. Arpad I. Csurgay is a Visiting Professor at the EE Department - Center for Nano Science and Technology, from Pazmany Peter Catholic University, Budapest, Hungary, (Department of Information Technology)

2. X-rays Ultraviolet Visible light Infrared IR Microwave Radio Audio ELECTROMAGNETIC WAVES Gamma-rays PHz THz GHz MHz kHz

3. SOME IMPORTANT APPLICATIONS OF EM WAVES RADIO, TELEVISION, TELEPHONY WIRELESS RADIO, MOBILE PHONES RADAR (Radio Detecting And Ranging) RADIO ASTRONOMY IMAGING, TELESCOPES, MICROSCOPES MEDICAL IMAGING: X-RAY, CT, NMR, fMRI, etc OPTICS (Visible, Infrared, UV, Fiber Optics) MATERIAL STUDIES HIGH SPEED INTERCONNECTS (MULTI-CHIP TECHNOLOGIES) SOLAR ENERGY HARVESTING BIONIC (BI-ology + electrONIC) applications

4. z m, q z(t) y(t) y x(t) x Classical Physics The ‘space–time –body–force’ model Geometrical ‘space’ and ‘time’set the ‘theater’, where a‘bodies’are moved by ‘forces’. Four fundamental notions: space,time, body,force COLLISION (BODIES) VECTORIAL SUPERPOSITION (FORCES) ‘INTERFERENCE’ Space and Time Trajectory: Force in EM field : F, N, E V/m, q As, v m/s, B Vs/m2

5. e - e 0.1 nm 1 nm INTERACTION ENERGY 0,18 V 2 nm INTERACTION ENERGY 14,7 V Coulomb-coupling on the nanoscale is STRONG. Dipole – Dipole Interaction NATURE HAS BEEN HIDING ELECTROMAGNETIC FORCES FOR THOUSENDS OF YEARS MAN DID NOT KNOW THAT LIGHT IS EM WAVE BODIES FROM OUTSIDE LOOKED LIKE NEUTRAL EVERYDAY EXPERIENCE: GRAVITY

6. Proton Electron r GRAVITATIONAL FORCE ELECTROSTATIC FORCE

8. MAXWELL’S EQUATIONS In free space (Vacuum) Gauss’s Law for Electric Field Gauss’s Law for Magnetic Field Faraday’s Law Ampere’s Law

9. Example: MOVING CHARGE Solution of the Maxwell’s Equations for large distances from Q CHARGE  ELECTRIC FIELD MOVING CHARGE (CURRENT)  ELECTRIC + MAGNETIC FIELD ACCELERATING CHARGE (CURRENT)  ELECTROMAGNETIC RADIATION (EM WAVE)

10. MAXWELL’S EQUATIONS In materials (“simple materials”) The EM field INDUCES additional sources (charges and currents), which also contribute to the EM field by conduction ( ), polarization ( ), and magnetization ( ). Gauss’s Law for Electric Field Gauss’s Law for Magnetic Field Faraday’s Law Ampere’s Law

11. Gauss’s Law for Electric Field Charge is the “source” of D Gauss’s Law for Magnetic Field There is no “source” of B (vector-lines are “closed”) Faraday’s Law “Induced” electric field (emf) Ampere’s Law

12. BOUNDARY CONDITIONS CONTINUITY EQUATION

13. ENERGY IN EM FIELDS ENERGY DENSITY LORENTZ FORCE (Mechanical force) CONSERVATION OF ENERGY IN EM FIELDS Power density emanating RADIATION Total power generated by the sources (batteries, generators, etc.) Rate if increase of electric and magnetic stored energy Power dissipated

14. EM energy stored in Volume V Dissipation in conductors Generators produce (+) or dissipate (-) energy/unit time Power leaves the volume through RADIATION Poynting vector

15. H E S = E x H THE EM WAVE CARRY ENERGY AND MOMENTUM ENERGY AND MOMENTUM ARE CONSERVED !