Negative Refractive Index And Metamaterial :Current Scientific

Progress and Applications

-Shiv Ashish Kumar

Outline

• Introduction of Metamaterial and NIM.• Concepts to reality• Structure for NIM• Application

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Metamaterial

• Meta means Beyond in greek• Meta material literally means beyond

conventional material.• They are typically man made material .• Having a properties not found in nature.

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Negative refractive index

In naturally exiting substances permittivity and permiability are positve (except the cases of noble metals like gold silver etc where permitivitty is negative for certain range of frequency).

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Now lets consider that :

( )( )effn n

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Negative refractive index

• So we see that a negative refractive index can be obtained in principle if both permittivity and permeability are negative simultaneously.

• This makes the left hand material.• Why we want negative refractive index ??

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Snell`s Law

Negative Refractive index

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Negative refractive index

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•Snell`s law is still valid

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Concept

•The first theoritical study was performed by V.G VESELAGO and it took nearly 30 years for experimental verification.

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Concepts to reality

D.R Smith has shown for the first time simultaneously negative Permeability and Permittivity

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Concepts to reality

Sir J.B Pendry has given the concept of perfect lens using negative refractive index.

This is one of the great break though work in the world of meta material.

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Concepts to reality

Till 2007, shortest Wavelength 725nm at which

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Different structures used for designingNIM.

• The famous SRR(split ring resonator suggested by Sir Pendry)

• First Realized by D.R Smith group in 2001.

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Structure for NIM

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Structure for NIM

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Negative Refractive index in optics

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Application

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Applications

Cloaking

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Applications

Watching your back !!

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Problems

High Dissipative losses is a big problem and limits the application .

We are still far from having a practical device.

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The famous people in the world of meta material

• V.G Veselago • Sir John Brian Pendry , imperial

college ,London.• Professor David R. Smith ,Duke University• Vladimir M. Shalaev , Perdue university.• Xiang Zhang , University of

California ,Berkeley.

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