Scattering matrix model of complex horn-antenna launchers by FDTD method

In this paper, by modifying defects in a photonic crystal lattice, a two-dimensional photonic crystal horn antenna is designed. The photonic crystal used for this purpose is composed of a hexagonal lattice of circular holes in a dielectric slab. The results of this paper allow us to design a photonic crystal antenna capable of separating TE and TM modes. The designed structure has a very simple design that allows low cost fabrication. The structure is numerically simulated using a finite-difference time-domain (FDTD) method. Its wide bandwidth, its low loss and the ability to transmit waves at a terahertz frequency range are the antenna’s main advantages. The return loss for the frequency range of 180 to 215 THz is from –6.63 to –28.3 dB. Moreover, a 35 THz bandwidth is obtained for this structure.

Download Full-text

The Scattering Matrix Model of the Quasioptical Resonator Coupled to A Single Mode Waveguide

2006 16th International Crimean Microwave and Telecommunication Technology ◽

10.1109/crmico.2006.256102 ◽

2006 ◽

Cited By ~ 1

Author(s):

V. Glamazdin ◽

M. Natarov ◽

V. Skresanov

Keyword(s):

Matrix Model ◽

Single Mode ◽

Scattering Matrix ◽

Quasioptical Resonator ◽

Single Mode Waveguide

Download Full-text

“Preparation of Single Crystalline Gold Films for ED Studies”

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100096424 ◽

1972 ◽

Vol 30 ◽

pp. 634-635

Author(s):

Joseph D. C. Peng

Keyword(s):

Crystal Morphology ◽

Diffraction Theory ◽

Scattering Matrix ◽

Vacuum Evaporation ◽

Gold Films ◽

Matrix Formulation ◽

Silver Films ◽

Single Crystalline ◽

Grating Pattern ◽

Stacking Disorder

The relative intensities of the ED spots in a cross-grating pattern can be calculated using N-beam electron diffraction theory. The scattering matrix formulation of N-beam ED theory has been previously applied to imperfect microcrystals of gold containing stacking disorder (coherent twinning) in the (111) crystal plane. In the present experiment an effort has been made to grow single-crystalline, defect-free (111) gold films of a uniform and accurately know thickness using vacuum evaporation techniques. These represent stringent conditions to be met experimentally; however, if a meaningful comparison is to be made between theory and experiment, these factors must be carefully controlled. It is well-known that crystal morphology, perfection, and orientation each have pronounced effects on relative intensities in single crystals.The double evaporation method first suggested by Pashley was employed with some modifications. Oriented silver films of a thickness of about 1500Å were first grown by vacuum evaporation on freshly cleaved mica, with the substrate temperature at 285° C during evaporation with the deposition rate at 500-800Å/sec.

Download Full-text