Optical Ring Resonator (FDTD Animation)

Here, we demonstrate the propagation phenomena in a double optical ring resonator structure. A windowed cosine excitation is pumped in the bottom dielectric straight waveguide and as this input mode propagates past the circular waveguides, the optical coupling occurs yielding wave propagation in the circular waveguide. The structure is chosen for illustration purposes only and it is possible to see several coupling between the circular and straight waveguides. In practice, various combinations are used to obtain optical filtering. For more information, you can check the wikipedia page


Also see below:
Oblique Plane Wave Reflection From Half Space
Radiation from a Circularly Tapered Dielectric Waveguide
Right Hand Circular Polarization (RHCP) Animation
Linear Polarization Animation
Left Hand Elliptical Polarization (LHEP) Animation
Standing Wave Pattern (SWR) Animation
Electromagnetic Propagation of UWB Short Pulse in Random Medium 
Half Wavelength Dipole Antenna Radiation 
Dipole Antenna Radiation 
Dish Antenna Animation (Parabolic reflector) 
FDTD Simulation of a Half Convex Lens
Diffraction from a Single Slit (FDTD Animation)
Ground Penetrating Radar (GPR) B-Scan Collection (FDTD Animation )
Ground Penetrating Radar (GPR) FDTD Animation

Ground Penetrating Radar (GPR) B-Scan Collection (FDTD Animation )

Here, B-scan data collection of a simple ground penetrating radar (GPR) is animated through the use of Finite-difference time-domain (FDTD) method. The upper part of the animation shows the 2D spatial propagation of the short pulse transmitted from the antenna at different spatial locations. The transmitting antenna shoots a short electromagnetic pulse (with a central frequency of 600 MHz) into the subsurface where the relative dielectric permittivity is 4. The short pulse is reflected from the air-soil interface and then from the target embedded in the subsurface. Then, the scattered signals are recorded by the same antenna in the receiving mode. The lower part of the animation corresponds to the received signals (A-scan) at the same antenna for each of the positions. This constitutes the so-called B-scan data collection.

Standing Wave Patterns in Medium with Multiple Interfaces

The generation of standing wave patterns in a medium with three different dielectric permittivities. The reflection and transmission along the two interfaces are shown. Since there are infinitely many reflections, only the overall left and right traveling and the total waves are shown in the animation. When the total traveling field is plotted in space at different time instants (as in the bottom figure), the standing wave patterns can easily be observed.

For similar animations involving a single interface, see below:



Standing Wave Pattern (SWR) and Propagation in Lossy Medium

Standing Wave Pattern (SWR) and Propagation in a Lossless Medium

Standing Wave Pattern (SWR) and Propagation in Lossy Medium

This animation serves as complementary to a previously uploaded one (http://www.youtube.com/watch?v=s5MBno0PZjE) where the medium were lossless. This time, the medium onto which the wave is impinging is lossy and we demonstrate the time-domain propagation of a uniform plane wave traveling in the +z direction and normally incident on the medium interface (at z=0). Again, only the electric field intensity is shown.

The top figure shows the incident (blue), reflected (red), incident+reflected (teal) and transmitted field in both media. In the bottom figure, the standing wave patterns created in both media are shown. Also, the decaying nature of the electromagnetic wave due to lossy nature of the medium is evident in the lossy medium.