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1. METAMETERIALS

2. CONTENTS
What is Metamaterial?
Metamaterials Vs Natural Materials.
Brief History of Metamaterial Research.
Classification of Metamaterials.
Applications of Metamaterials.
Metamaterial RD.
Conclusion.

3. WHAT IS
METAMETERIALS
The term Metamaterial is first
coined by Roger M
Walser, University of Texas at
Austin in 1999.
A Metamaterial(MM) is a
macroscopic composite of
periodic or non-periodic
structure whose function
is due to both the cellular
architecture as well
as the chemical composition.
They exhibit properties
generally not found in
nature.

4. Metamaterials Vs Natural Materials
Metamaterials
gives us the
opportunity to
realize
all possible
material properties
by designing
different cellular
architecture and
using
different material
substrates.
Most of the natural
materials occur at
discrete
points, so most of the
material properties have
to be realized using
metamaterials.

5. Metamaterials Vs
Natural Materials
• Possible unique functionalities for
Metamaterials
• the point µ -µ0 and e -e0 represents an
anti-air in the LHM region, which will produce a
perfect lens.
• The point µ 0 and e 0 represents a nihility,
which can yield a perfect tunneling effect.
• The line µ e in both RHM and LHM regions
represents impedance-matching materials, which
have perfect impedance matching with air,
resulting no reflections.

6. Brief History of Metamaterial Research

7. Brief History of Metamaterial Research
Pendry et al in 1996 used an artificial wired
medium whose permittivity is negative to
realize
artificial electric plasma, followed by this in
1999 magnetic plasma is realized whose
permeability is negative, using split-ring
resonators (SRR).
In 2005 Smith et al realized gradient
refractive
index medium to bend electromagnetic
waves. In
2006 optical transformation is proposed to
control and manipulate electromagnetic
waves and
proposition of invisible cloak.

8. Classification
of
Metamaterials

9. Application of Metamaterials
 Metamaterial as antenna
 Metamaterial coatings have been used to enhance the radiation and matching properties
of electrically small electric and magnetic dipole antennas. Metamaterial step up the
radiated power. The newest metamaterial antenna radiate 95% of input radio signal at
350 MHz Experimental metamaterial antenna are as small as one fifth of a wavelength.
Patch antenna with metamaterial cover have increased directivity. Flat horn antenna
with flat aperture constructed of zero index metamaterial has advantage of improved
directivity. Zero-index metamaterials can be used to achieve high directivity antennas

10. Metamaterial as cloaks
 Cloaking can be achieved by cancellation of the electric and magnetic field generated
by an object or by guiding the electromagnet wave around the object. Guiding the wave
means transforming the coordinate system in such a way that inside the hollow cloak
electromagnetic field will be zero this makes the region inside the shell disappear.

11. Terahertz Modulators
• Natural materials do not respond to Terahertz
frequency, also called Terahertz gap.
• A high passive modulation of the LC resonance has
been achieved which can used to design terahertz
modulators.
• -Zhang et al., OSU

12. Metamaterial Absorber
• It uses the loss components of permittivity and
magnetic permeability to realize a medium which
has high radiation absorption ratio.
• They have advantages over conventional absorbers
on enhanced miniaturization, increased
adaptability and effectiveness.
• These have application in emitters, sensors,
spatial light modulators, infrared camouflage,
thermophotovoltaics, etc.

13. Elastic
Metamaterials

14. Conclusion
Theoretically metamaterial can have desired value
of µ and e. They can different properties
and put to different applications.
It is due to Metamaterials that several phenomena
that would undoubtedly have been considered
science fiction only a few years ago have been
explicitly demonstrated.
Though, many fascinating linear and nonlinear
phenomena taking place in metamaterials have been
theoretically predicted that still remain to be
experimentally demonstrated.

15. THANKS