chip spintroincs theory

8/14/2019 Chip Spintroincs Theory

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RELATIVISTIC CHIPS:RELATIVISTIC CHIPS:THE SPINTRONICS THEORYTHE SPINTRONICS THEORY


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TOPICS OF DISCUSSIONTOPICS OF DISCUSSION

The Topics of Discussion are :

1. Birth of A New Era.

2. Relativistic Chips: The Concept.3. Spintronic Chips: The Technology.

4. Spintronics Devices.

5. Limitations.

6. Conclusion.


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INTRODUCTIONINTRODUCTION

No microprocessor of the world can challenge

BRAINBRAIN, the ultimate biochemical machine.

Moores law still holds good.Heat and energy are the two main constraints of

the present IC technology.

Relativity may be the Answer.

Even the worlds fastest computers are not very

faster, but the electrons in them do.


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RELATIVISTIC CHIPS:THE CONCEPTRELATIVISTIC CHIPS:THE CONCEPT

Einstein proposed the THEORY OF RELATIVITY.

THOERY OF RELATIVITY suggests a new design for

microchips that relies on the spin of electrons.These so-called relativistic effects are all minuscule,

however, unless the object accelerates to a significant

fraction ofc, which is about 300 million meters per second.

Though the high end chips are not as fast as light but theelectronselectrons inside them do.

Contd


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SPINTRONICS:THE TECHNOLOGYSPINTRONICS:THE TECHNOLOGY

SPINTRONICSSPINTRONICS, short for spin electronics, is the study of electron spin

in materials in order to better understand its behavior, with the hope of

developing an entirely new generation of microelectronic devices.

MR. ELECTRONMR. ELECTRONTwo parts ofTwo parts of

his personality!!!his personality!!!

SPINSPIN

CHARGECHARGE


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An electron is just like such a spinning sphere of charge.

The electron has a quantum property, called spin, that makes it

behave almost as if it were a magnet twirling about the axisconnecting its north and south poles. Electrons (spheres) can

have spins oriented in different directions.


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A magnetic field causes an electron

to swivel like the needle of a

compass to line up with the field

(left). But the spin axis also

precesses like a wobbling top

(right).

When the magnetic field isremoved, the electron stops

precessing and locks the orientation

of its spin.


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SPINTRONICS DEVICESSPINTRONICS DEVICES

The Spintronic devices have opened us to a whole new world of

high-tech technology. Some of these devices to name are:

RELATIVISTIC TRANSISTORS.RELATIVISTIC TRANSISTORS.

MRAM (MAGNETIC RANDOM ACCESSS MEMORY).MRAM (MAGNETIC RANDOM ACCESSS MEMORY).

TRANSPINNORS.TRANSPINNORS.

SPINTRONIC SOLAR CELLS.SPINTRONIC SOLAR CELLS.


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SPIN FET was proposed in 1990 by Supriyo Datta and Biswajit A.

Das, at Purdue University, in West Lafayette.

They proposed a current modulator device based on the electric

field modification of spin precession in a narrow gap

semiconductor. In this device, the spin-polarized electrons would

be injected with the use of a ferromagnetic electrode that forms an

ohmic contact with the semiconductor and would be detected with

a second ferromagnetic electrode (spin analyzer) contact.

RELATIVISTIC TRANSISTORSRELATIVISTIC TRANSISTORS


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MRAM (Magnetic RAM)MRAM (Magnetic RAM)

MRAMMRAM stands forMMagnetic RRandom AAccess MMemory.

It places the magnetic domains on the surface of a silicon chipand places a magneto-resistive sensor beneath every one ofthem. Just like a hard disk, the information stored in themagnetic domains is non-volatile. It is not lost when the powergoes off.

The two main concept that govern MRAM technology are:

Giant Magnetoresistance (GMR) effect The Tunneling Magneto-Resistive (TMR) effect

Contd


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GAINT MAGNETORESISTANCE TUNNELING MAGNETO-

EFFECT RESISTIVE EFFECT


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OPERATIONOPERATION

To write to the memory cell, a current pulse in the bit linegenerates a localized magnetic field that sets the free magnetic

layer into the appropriate orientation for a 0 or a 1, while the

other magnetic layer is held with a fixed orientation. To read the

memory cell, a current is passed through it via the selectiontransistor to measure its resistance.


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TRANSPINNORSTRANSPINNORS

A Transpinnor is a bridge of four

electrically connected GMR(giant

magnetoresistive) films whose resistance

is controlled by the magnetic field from

the current in one or more input striplineselectrically isolated from the GMR films.

Transpinnors can be used as selection-

matrix elements for magnetic memories,

for logic elements of all kinds (e.g., AND,OR, XOR, NAND, NOT), for amplifiers,

differential amplifiers.


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SPINTRONIC SOLAR CELLSSPINTRONIC SOLAR CELLS

Based on principle of the spin-polarized P-N junction


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LIMITATIONSLIMITATIONS

Every technology comes with its own short comings.

Much remains to be understood about the behavior of

electron spins in materials for technological applications.HAZARDS OF HOLES.

Fundamental challenges of creating and measuring spin,

understanding better the transport of spin at interfaces.

Scope of the present IC fabrication technology.


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CONCLUSIONCONCLUSION

A number of spin-based microelectronic devices have been

proposed, and the giant magneto-resistive sandwich structure is

a proven commercial success, being a part of every computer

coming off the production line.

Spintronic-based nonvolatile memory elements may very well

become available in the near future.

Limitations had always made MAN to go beyond the horizon.

Somebody had very rightly said

Limitations are not there to tip you Off but only for BoostingLimitations are not there to tip you Off but only for Boosting

You UpYou Up


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QUESTIONS ?QUESTIONS ?


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THANK YOUTHANK YOU

chip spintroincs theory

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