Lens Effect with Photonic Crystals

unkindnesskindUrban and Civil

Nov 15, 2013 (3 years and 9 months ago)

65 views

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Lens Effect with Photonic Crystals

Student “#3”

ECEN 5616 Final Project Presentation

12.07.2010

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Overview


Introduction


Negative Refractive Index


Photonic Crystal


Superlens


Methods


Results

2

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Introduction

3

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Negative Refractive Index


V. G.
Veslago

(1968)


Negative permittivity and negative permeability


Real index of refraction


Electric resonance in material


Strong magnetic resonance in material


Metals exhibit negative permittivity below

characteristic plasma frequency


Requires electric resonance and

strong magnetic resonance


No negative refractive index

material in nature


4

n<0

n>0

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Photonic Crystal


Periodic optical nanostructures




Analogous to semiconductor crystal


The feature sizes are comparable to the
wavelength

5









r r R
r r R
 
 
 
 
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Waves in Periodic Media

6



















0
0
H r i r E r
E r i r H r
H r
r E r



 
  
 
 
 
 

Maxwell’s Equations:






Bloch Function


due to translational periodicity









2 2
0
E r E r r E r

 
   
 






2
0
1
H r H r
r


 
  
 
 




i k R
k k
E r R E r e

 
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Lattice Structure

7


Brillouin

zones

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Photonic Band Structure

8

x
k
y
k
Negative effective index region

c
a
Self
-
collimation

Self
-
collimation

Bandgap

Effective medium

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Superlens

9


Perfect, real

image


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Method & Results

10

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Finite Difference Time Domain
(FDTD): MEEP


Numerical method in time domain


Calculates E field and H field in every point of the
computational domain as they evolve in time


Can specify materials


Wide range of frequencies can be

explored at once



11

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Results

12

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Results

13

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Results

14

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Current Research

15

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Thank you