# Lens Effect with Photonic Crystals

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15 Νοε 2013 (πριν από 4 χρόνια και 6 μήνες)

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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

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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

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Brillouin

zones

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Photonic Band Structure

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x
k
y
k
Negative effective index region

c
a
Self
-
collimation

Self
-
collimation

Bandgap

Effective medium

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Superlens

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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

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Thank you