quantum comp 19march

8/3/2019 Quantum Comp 19march

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| QUANTUM COMPUTERS .}| QUANTUM COMPUTERS .} BEYOND THE LIMITS

BY:BH ARAT H KUMAR K MBH ARAT H KUMAR K M1DS06TE037.1DS06TE037.

TELECOMMUNICATION.DSCE,B ENGALURU.

GUIDE: MR. JAYANT H .C MR. JAYANT H .CDEPT. OF TELECOMDSCE.


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Babbagesdifferenceengine.

A silicon chip What next??


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AGENDAAGENDA

Moores law and limitations.Quantum computer?Data representation

Important aspects in quantum computer.classical computer v/s quantum computers.Benefits of quantum computers.Problems in construction of quantum computers.conclusion


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Moores LawMoores LawIn 1965, Gordon Moore predicted that number

of transistors per square inch on integrated circuitshad doubled every year since the integrated circuit was invented.

This has held true .. So far

But, this would not remain true for much longer.

The ability to put transistors on chips wasapproaching the atomic level.

If scale becomes too small, Electrons tunnelthrough micro-thin barriers between wirescorrupting signals.

Fig. Gordon Moore


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FORGET CLASSICAL FORGET CLASSICALTHINK QUANTUM THINK QUANTUM


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Fig. Richard Feynman

1982 - Feynman proposed the idea of creatingmachines based on the laws of quantummechanics instead of the laws of classical physics.

1985 - David Deutsch developed the quantumturning machine, showing that quantum circuitsare universal.

1994 - Peter Shor came up with a quantumalgorithm to factor very large numbers in

polynomial time.

1997 - Lov Grover develops a quantum searchalgorithm.

Milestones


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QUANTUM COMPUTERS

A next generation of classical

computers.

uses quantum mechanical phenomena-

superposition and entanglement.

Faster than classical silicon computers.

Worlds greatest calculation on

quantum computer is 3 times 5

equals 15 !!!


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Quantum Computer ComponentsQuantum Computer Components

Qubit s or q u an tum bit- ena bl es yo u t o m an ipula t e 2+ va lu es a t th e sa m e tim eMic ro p ro cessor t o s t ore infor m a tion

Ph o t ons ( lasers) for fas t & long d is t an ce in t era ctions


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QUBITS (QUBITS ( |0>|0> ,, |1>|1> ))

F ig. Representation of a qubit,the fundamental buildingblock of quantum computers.

information as quantum bits or qubits .

Its a building block of quantum computers.

A qubit is a bit of information that can be both zero and onesimultaneously.

atoms, ions, photons or electrons and their respective controldevices -together acting as computer memory and a processor.

Due to multiple states more powerful than today's most powerful supercomputers.


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Bits v/s QubitsBits v/s Qubits


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Representation of dataRepresentation of data- - qubitsqubitsA physical implementation of a qubit could use the two energy levels of an atom.An excited state representing |1> and a ground state representing |0>.

ExcitedState

Ground StateNucleus

Light pulse of frequency P

for timeinterval t

ElectronState |0> State |1>

Nucleus


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Superposition & EntanglementsSuperposition & EntanglementsSuperposition means a system can be in two or more of its states

simultaneously.

A single qubit can be forced into a superposition of the two statesdenoted by the addition of the state vectors: |] > = E |0> + |1>

Superposition gives quantum computers an inherent parallelism.

A 30-qubit quantum computer would equal the processing power of a conventional computer that could run at 10 teraflops.

State |0> + |1>Nucleus


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SuperpositionSuperpositionThe particle has wave-like properties.

Interference can cause the particle to act in ways

that are impossible to explain without these wave-

like properties.

The ability for the particle to be in a

superposition is where we get the parallel

nature of quantum computing.

If each of the states corresponds to a different

value then, if we have a superposition of such

states and act on the system, we effectively act on

all the states simultaneously.


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A B C

0 0 0

0 1 0

1 0 0

1 1 1

I nput Output

A

BC

Ex.

Th e AND Ga t eI

n these 3 cases,information isbeing destroyed

Reversible logic.

Reversible--their original input state can be derived from their output state,uniquely

deterministic computation can be performed on a quantum computer only if itis reversible.

Luckily, it has been shown that any deterministic computation can be madereversible.(Charles Bennet, 1973)


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A Universal Quantum ComputerA Universal Quantum Computer

The CCN gate has been shown to be a universal reversible logic gate as it can beused as a NAND gate.

A - Target

B - Control 1

C - Control 2

A B C A B C0 0 0 0 0 0

0 0 1 0 0 1

0 1 0 0 1 0

0 1 1 1 1 1

1 0 0 1 0 0

1 0 1 1 0 1

1 1 0 1 1 0

1 1 1 0 1 1

I nput OutputA

B

C

When our target input is 1, our target outputis a result of a NAND of B and C.


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Entanglements.Entanglements.

Fig. entangled photons

Correlations between states within a superposition.

Referred to as a parallelism of states.

Transfer of this entangled quantum state to an arbitrarydistant location is tele-transportation entanglementassisted.


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H ow does it Work ???A quantum computer uses molecules and atoms to do thecomputations required.Using Nuclear Magnetic Resonance (NMR) techniques,scientists nowadays can manipulate the spin of an atom.


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QU ANTUM PROCE SS ORQU ANTUM PROCE SS OR


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Quantum Computing Parallelism

The most exciting feature of quantum computing is quantum parallelism.

Parallelism allows a quantum computer to work on amillion computation at once.


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Classical computers v/s Quantum computersClassical computers v/s Quantum computersThe memory of a classical computer is a

string of 0s and 1s.

it can perform calculations on only oneset of numbers simultaneously.

parallel computing is performed byhaving several processors linked together.

The memory of a quantum computer is a

quantum state that can be a superposition of

different numbers.

A quantum computer can do an arbitrary

reversible classical computation on all the

numbers simultaneously.

a single quantum processor is able to

perform multiple computations on its own


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Benefits of quantum computersBenefits of quantum computersArtificial Intelligence.

complex compression algorithms for voice and image recognition.

achievement of true randomness.

Molecular simulations.

Ultra secure and dense communication.

Quantum networking


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Where do quantum computers fit inWhere do quantum computers fit in ..(quantum complexity theory.)(quantum complexity theory.)

Fig. where exactly quantum computers fit in.

Fig.D-Wave's 16-qubitquantum computer


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I ssues in the production of quantum computers.I ssues in the production of quantum computers.

Quantum Decoherence( unwanted interaction between a quantum computer and

its environment, which introduces errors)

H ardware for quantum computers.

Need for an efficient quantum programming language.


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INEVITABILITY FOR QUANTUM COMPUTERSINEVITABILITY FOR QUANTUM COMPUTERS

Scaling

Energy

Economic


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CONCLUSIONCONCLUSION

When processor components reach atomic scale, Moores Law breaks down.

Quantum effects become important whether we want them or not.

But huge obstacles in building a practical quantum computer!

Making a practical quantum computing is still far in the future and is just a matter of time.

Quantum Computing could provide a radical change in the way computation is performed.

The advantages of Quantum Computing lie in the aspects of Quantum Mechanicsthat are peculiar to it

This will be one of the biggest steps in science and will undoubtedly revolutionizethe practical computing world.


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ReferencesReferences1. BIO-QUANTUM COMPUTING. The generalscience journal by Paolo Manzelli.2.QUANTUN COMPUTERS BY Neil Gershenfeld(MIT) and Isaac Chuang (IBM Almaden ResearchCenter).3. The Temple of Quantum Computing by Riley T.Perry Version 1 : 1.4. http://www.i-sis.org.uk/QuantumComputing.php

5. http://en.wikipedia.org/wiki/Quantum_computer 6. Quantum computation Samuel L. BraunsteinComputer Science, University of York, York


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quantum comp 19march

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