Attenuation in Left-handed Waveguide Structure by Equivalent Current Theory Method

Hana M. Mousa^1, and Mohammed M. Shabat²

¹Physics Department, Al Azhar University, Gaza Strip, Palestinian Authority

²Physics Department, Islamic University, Gaza Strip, Palestinian Authority

Cite this paper:
Hana M. Mousa and Mohammed M. Shabat. Attenuation in Left-handed Waveguide Structure by Equivalent Current Theory Method. Applied Mathematics and Physics. 2015; 3(1):1-5. doi: 10.12691/amp-3-1-1

Abstract

In this work, the propagation and attenuation characteristics of both TE and TM waves in a waveguide structure consisting of left handed material (LHM) film by using the equivalent current theory of optical waveguide coupling method have been derived and obtained. The dispersion relations and the attenuation coefficient were numerically solved for a given set of parameters: allowed phase angles; core’s thicknesses; and propagation constants. We found that lower attenuation is realized for higher propagation constants. Moreover, attenuation coefficient has same small positive values for all thickness in phase angles range of values (0⁰-57⁰). Besides that, the attenuation decreases to negative values with thickness increase in phase angles range of values (57^0-59⁰) which means a gain of the wave is achieved for wider buffer layer and at larger phase angles. We also found that, TE waves have lower attenuation than that of TM waves.

Keywords:
attenuation dispersion equivalent current theory left handed material

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