+ lens effect with photonic crystals student “#3” ecen 5616 final project presentation...

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Lens Effect with Photonic Crystals Student “#3”

ECEN 5616 Final Project Presentation12.07.2010

2+Overview

Introduction Negative Refractive Index Photonic Crystal Superlens

Methods

Results

3

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Introduction

4+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 belowcharacteristic plasma frequency

Requires electric resonance andstrong magnetic resonance

No negative refractive index material in nature

n<0

n>0

5+Photonic Crystal

Periodic optical nanostructures

Analogous to semiconductor crystal

The feature sizes are comparable to the wavelength

r r R

r r R

6+Waves in Periodic Media

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 20E r E r r E r

20

1H r H r

r

i k Rk kE r R E r e

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7+Lattice Structure

Brillouin zones

8+Photonic Band Structure

xkyk

Negative effective index region

ca

Self -collimation

Self -collimation

Bandgap

Effective medium

9+Superlens

Perfect, real image

10

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Method & Results

11+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

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Results

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Results

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Results

15+Current Research

16

Thank you