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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

+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 Rr r R

6+Waves in Periodic Media

00

H r i r E rE r i r H rH r

r E r

Maxwell’s Equations:

Bloch Function due to translational periodicity

2 20E r E r r E r

20

1 H r H rr

i k Rk kE r R E r e

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

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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

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Thank you