Showing posts with label one-dimensional photonic crystal. Show all posts
Showing posts with label one-dimensional photonic crystal. Show all posts

Monday, April 8, 2019

Abstract-The properties of a tunable terahertz multichannel filter from one-dimensional photonic crystal dope by magnetized plasma defect


Mei-chen, XuSong Liu, Shuang-ying Zhong,

https://link.springer.com/article/10.1007%2Fs11082-019-1826-8

The terahertz magnetize-field tunable filtering properties in a multichannel filter based on a one-dimensional photonic crystal doped by magnetized plasma are theoretically investigated. The considered structure of (AB)4(ACB)N(AB)4 is designed, where A and B are two dielectric layers, C is the plasma layer, and N is the defect number. First, the structure can be worked as a multichannel filter whose channel number equals N. Second, the defect mode frequencies are all red-shifted as the ratio of dielectric refractive index or the sum of the A and B layer length increases. Third, we find that the channel frequencies can be shifted as a function of the applied magnetic field and the defect mode frequencies are all red-shifted as the plasma density increases. And the thickness of a plasma layer also affects the intensity, position and number of the defect modes. Therefore, these unusual properties may provide a novel design idea of a tunable terahertz multichannel transmission filter in future.

Tuesday, November 14, 2017

Abstract-Superconductor based ternary periodic multilayered structure as a single and multichanneled filter in the terahertz region



Nirmala Maria D’souza and Vincent Mathew

https://www.osapublishing.org/ao/abstract.cfm?uri=ao-56-24-6765&origin=search

A single as well as a multichanneled filter in the terahertz region has been proposed by designing a one-dimensional photonic crystal (PhC) structure using a high-temperature superconductor air-dielectric ternary periodic structure. The filter is designed without incorporating any defect, which has rarely been proposed in a ternary PhC structure. The theoretical study of transmittance was performed by applying the transfer matrix method. The transition from single channel to desired multichannel is achieved by adjusting the number of periods. Furthermore, the impact of the thicknesses and dielectric constants of the constituting layers was investigated. In addition to this, the tunability is achieved by the influence of temperature-dependent dielectric constant of the superconductor.
© 2017 Optical Society of America