Topological spintronics

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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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