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A degenerate band edge is a resonant dispersive behavior of coupled transmission lines arising from a fourth-order degeneracy due to the coalescence of two propagating and two evanescent modes. It leads to a so-called giant resonance resulting in field enhancement inside the transmission line. In this paper, we propose a SIW periodic line supporting a degenerate band edge and we study the impact of losses. Conductor and dielectric losses are analyzed in the full-wave simulations of the unit cell and of truncated structures.
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Sensitivity of resonance frequency in the detection of thin layer using nano-slit structures
Abstract We derive the formulas for the resonance frequencies and their sensitivity when the nano-slit structures are used in the detection of thin layers. For a thin layer with a thickness of $$H$$ deposited over the nanostructure, we show quantitatively that for both single and periodic slit structures with slit aperture size $$\delta $$, the sensitivity of resonance frequency reduces as $$H$$ increases. Specifically, the sensitivity is of order $$O(\delta /H)$$ if $$H>\delta $$ and of order $$O(1+\ln H/\delta )$$ otherwise. The evanescent wave modes are present along the interface between the thin dielectric film and ambient medium above. From the mathematical derivations, it is observed that the sensitivity of the resonance frequency highly depends on the effect of evanescent wave modes on the tiny slit apertures.
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- PAR ID:
- 10221166
- Date Published:
- Journal Name:
- IMA Journal of Applied Mathematics
- Volume:
- 86
- Issue:
- 1
- ISSN:
- 0272-4960
- Page Range / eLocation ID:
- 146 to 164
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1093/imamat/hxaa041
