terahertz sensing with spoof plasmonic devices oral... · plasmonics: simple process where one can...
TRANSCRIPT
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Terahertz Sensing with
Spoof Plasmonic Devices
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Content1.Introduction of project
2.Methodology 1 and 2
3.Results and Discussion 1 and 2
4.Conclusion
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1. Introduction:Current Methods: Gas or chemical sensing are not portable and complex
Plasmonics: Simple process where one can just shine light onto the sample and is portable
Purpose: Push the plasmonic sensing to low frequency such as the terahertz frequency to address the limitations of current methods
Aim: To create the design for the Spoof LSPs and ESPPs
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1. IntroductionProblems of current methods:
1. Complex
2. Energy inefficient
3. Not portable
Aims of project:
1. Portable
2. Cost effective
3. Simple
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2.1 Methodology for Spoof Localised surface plasmons (LSPs)Overview: The 2D structure consists of an inner cylinder of radius r overlaid with radial grooves of height h=R-r, width a, and periodicity d = 2pi(R/N), where N is the total number of grooves. The number of grooves and radius of the cylinder are chosen to satisfy. The grooves are filled with a dielectric of refractive index ng, and the surrounding medium is air.
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2.1 Methodology for Spoof Localised surface plasmons (LSPs)Step 1: Open COMSOL Multiphysics and this page would be seen
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2.1 Methodology for Spoof Localised surface plasmons (LSPs)Step 2: Click global definitions and define variables and values
Parameters
R: Large Radius
E: Electric Field of incident wave
S: scattering cross-section of incident wave
r: small radius
d: periodical distance between 2 red circles at the sidea
a: distance between 2 tubes
Hh: R-r
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2.1 Methodology for Spoof Localised surface plasmons (LSPs)Step 3: Click structure and build a model
Step 4: Choose the shape of the circle and add and define the parameters
Step 5: Choose the shape of a square and define it
Step 6: Choose the shape of a rectangle and define it (repeat step 4 times)
Step 7: Choose the shape of a square and define it (repeat the step 4 times)
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2.1 Methodology for Spoof Localised surface plasmons (LSPs)Step 8: Create the spiral shape and the design will look like this
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2.1 Methodology for Spoof Localised surface plasmons (LSPs)Step 10: Det white as matter and grey as air
Step 11: Click EMW and under domain selection all domains and select 5
Step 12: Click settings and solve for scattered field
Step 13: Click settings and solve for scattered field
Step 14: Add mesh
Step 15: Start Simulation
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3.1 Results and Discussion for spoof LSPsAfter simulating for 24 hours, the results are as shown below
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3.1 Results and Discussion for spoof LSPsAfter simulating for 24 hours, the results are as shown below
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2.2 Methodlogy for Effective Surface Plasmon Polaritons (ESPPs)- Making induced ESPPs through dielectric waveguide structures where transverse electric modes are transformed into ESPPs.
- A rectangular waveguide with a cresent shaped dielectric cylinders inserted into the waveguide.
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Waveguide structure
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Crescent structure
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Final structure
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4. ConclusionAll in all, materials respond to light at different frequency and a novel design for spoof LSPs and ESPPs has been developed in this project. Furthermore, this method to measure the terahertz sensing of different materials which is better than current methods