GUIDED BY, SUBMITTED BY,
Mrs.RAFEEKHA M.J. ANCY RAJU
ASST.PROFESSOR S7 EC A
ECE DEPARTMENT ROLL NO:4
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INTRODUCTION
SPINTRONICS
TOPOLOGICAL INSULATOR
SMB6
KONDO EFFECT
ANGLE RESOLVED PHOTOEMISSION SPECTROSCOPY
ADVANTAGES
DISADVANTAGES
APPLICATIONS
FUTURE SCOPE
CONCLUSION
REFERENCES
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The discovery of new materials with novel
properties is one of the most fascinating aspects of
physics.
Such findings lead to new research area in
spintronics
A very recent example of new materials is the
topological insulators.
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Conventional electronics uses charge of electron.
Spin based electronics incorporates spin of electron.
Spin is the intrinsic property of an electron.
Spin can exist one of the two states up or down.
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Controlling electron spin can be achieved with materials
called topological insulators.
Behave as insulators on the inside,but are highly
conductive on their surface.
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A new class of topological insulator is Topological Kondo
Insulator .
As insulators are cooled to absolute zero,their ability to insulate
effectively becomes infinite.
Under these conditions,some insulators atypically retain a tiny
bit of conductivity.These materials,termed Kondo Insulators.
In contrast to other 3D topological inulator,a TKI is truly
insulating in the bulk.
The strong electron correlations are present in the system,which
may interact with the novel topological phase.
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Topological kondo insulator.
It directly measures electron spin.
At high temperature(above 50k),its properties are typical
of a kondo metal,with metalic electrical conductivity
characterised by strong electron scattering.
At low temperature, it behaves as a non magnetic
insulator.
Its insulating behaviour based on Kondo effect.
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Scattering of conduction electrons in a metal due to magnetic
impurities resulting a charateristics change in resistivity with
temperature.
The effect arises from the interaction between a single
magnetic atom such as cobalt,and the many electrons in an
otherwise non-magnetic metal.
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Such an impurity typically has an intrinsic spin that
interact with the electron.
It prevents the flow of electrons from being
destroyed by irrgularities in the metal structure
Making SmB6 a very robust and efficient
topological ‘kondo insulator.
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Can control electron spin.
Increasing memory storage capacity.
Increasing processing power.
Consume less power.
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Manufacturing and implementing topological insulator
materials has been limited.
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Ultra low power electronics and spintronics devices.
Optoelectronic applications.
Memory storage and magnetic sensor applications.
Majorna fermion used in quantum computation.
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SKYRMIONS FOR QUANTUM COMPUTING
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MAGNETIZATION OF SKYRMION
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The research on today on the topological insulators
materials.
It is the best mechanism for creating ever smaller and
faster devices.
It offers an exciting stepping –stone into the a new era of
technologies.
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Nature Communication 30 July 2014 Ecole Polytechnique,
Federale de Lausanne.
Josh Schaefferkotter,Introduction of spintronics(2007).
Ando.Y ,Topological insulator materials(2013).
M Z Hasen and C L Kane (2010) Colloqium:topological
Insulators.
J E Moore (2010), The birth of Topological insulator
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