PHY 712 Spring Lecture 191 PHY 712 Electrodynamics 10-10:50 AM MWF Olin 107 Plan for Lecture 19: Start reading Chap. 8 in Jackson. A.Examples of waveguides B.TEM, TE, TM modes C.Resonant cavities 03/17/2013

PHY 712 Spring Lecture 19203/17/2013

PHY 712 Spring Lecture 193 Reminder:  Topic choices for “computational project” – suggestions available upon request -- due Monday March 24 th ? 03/17/2013

PHY 712 Spring Lecture 194 Fields near the surface on an ideal conductor 03/17/2013

PHY 712 Spring Lecture 195 Fields near the surface on an ideal conductor -- continued 03/17/2013

PHY 712 Spring Lecture 196 Fields near the surface on an ideal conductor -- continued 03/17/2013

PHY 712 Spring Lecture 197 Fields near the surface on an ideal conductor -- continued 03/17/2013

PHY 712 Spring Lecture 198 Boundary values for ideal conductor At the boundary of an ideal conductor, the E and H fields decay in the direction normal to the interface. H0H0 03/17/2013

PHY 712 Spring Lecture 199 Waveguide terminology TEM: transverse electric and magnetic (both E and H fields are perpendicular to wave propagation direction) TM: transverse magnetic (H field is perpendicular to wave propagation direction) TE: transverse electric (E field is perpendicular to wave propagation direction) 03/17/2013

PHY 712 Spring Lecture 1910 Wave guides Coaxial cable TEM modes Top view: a b  z (following problem 8.2 in Jackson’s text) Inside medium,  assumed to be real 03/17/2013

PHY 712 Spring Lecture 1911 Electromagnetic waves in a coaxial cable -- continued Top view: a b    03/17/2013

PHY 712 Spring Lecture 1912 Electromagnetic waves in a coaxial cable -- continued Top view: a b    03/17/2013

PHY 712 Spring Lecture 1913 Analysis of rectangular waveguide Boundary conditions at surface of waveguide: E tangential =0, B normal =0 z x y Cross section view b a 03/17/2013

PHY 712 Spring Lecture 1914 Analysis of rectangular waveguide z x y 03/17/2013

PHY 712 Spring Lecture 1915 Maxwell’s equations within the pipe: 03/17/2013

PHY 712 Spring Lecture 1916 Solution of Maxwell’s equations within the pipe: 03/17/2013

PHY 712 Spring Lecture 1917 TE modes for retangular wave guide continued: 03/17/2013

PHY 712 Spring Lecture 1918 Solution for m=n=1 03/17/2013

PHY 712 Spring Lecture 1919 Solution for m=n=1 k  03/17/2013

PHY 712 Spring Lecture 1920 Resonant cavity z x y 03/17/2013

PHY 712 Spring Lecture /17/2013 Resonant cavity z x y