• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

The Development Quantum Computing.

Extracts from this document...

Introduction

The Development Quantum Computing

ֿ

image00.png

In the beginning

        The story of computers started with the abacus invented by the Babylonians around 500 B.C.  In 1614 John Napier began to develop mechanical computers such as the Babbage differential engine that could carry out one fixed problem to the accuracy of 20 decimal places using steam power.  This is a picture of the left side of the Manchester Mark 1 computer, which was constructed in 1947.

image01.jpg

        However, computing didn’t advance until the introduction of vacuum tube powering in the early 20th century and transistors in 1947.  At present computers work by manipulating bits, that can only be of discrete values of 1 or 0.  In a digital computer the value of a bit is generated by the voltage on a capacitor, with a charged capacitor representing 1 and an uncharged capacitor denoting 0.  According to Moores law the number of transistors in computer chips doubles every 18 months and computers have been seen to double in speed and half in size every two years, this is due to advanced lithography that allows wires and transistors contained in chips to be one hundredth of the width of a human hair  These computers can carry out calculations using algorithms, a precise set of instructions used to solve a particular problem, an example of a fast or usable algorithm is addition and a slow or hard algorithm is factorisation.  There a limits to present computers, that can’t seem to be overcome by present technology.

...read more.

Middle

        It also increases storage capacity exponentially, as N qubits can store 2   numbers at once.  Imagine the   qubits are atoms whose different electronic states can be controlled by a tuned laser; this will change their state allowing in only one computational step a calculation to be performed on 2   different input numbers encoded in coherent superpositions of N qubits.  

        The actual space a quantum computer will take up will be significantly smaller than present day desk tops, allowing the further development of sophisticated, efficient palm held computers.  This is because given the right calculation each qubit can take the place of an entire processor, meaning that 100 barium ions could take the place of 100 computer processors.  

        Aside from computers quantum technology has developed rapidly in the last ten years.  In June 2002 a team of Australian scientist were able to teleport a laser beam, causing it to disappear and be regenerated 3 ft away, the results are yet to be confirmed but if they are sound this development could in a matter of years be able to teleport actual objects significant distances.  

Nuclear Magnetic Resonance

        After Shor’s discovery quantum computing construction began in earnest, however due to the phenomena of decoherence no atom or photon, being the qubit, can be of an undetermined state after being detected, the probabilities collapse and its state becomes definite.  This makes further calculations impossible as the exponential element of the qubit has been lost, causing it to behave as a regular analogous bit.

...read more.

Conclusion

        This demonstrates another quality of quantum computers NOT gates, which can operate on a combination of seemingly incompatible information.  Classical computers require two input gates as well as a simpler NOT gate to perform similar operations on classically compatible inputs.  

Alternatives to NMR

        Ions seem to be the answer to NMR’s problems.  There energy states can be determined using light and they can be controlled, by laser super cooling to micro Kelvin temperatures and positioned in ultra-high vacuum by electromagnetic forces that carefully control their 2 dimensional positions but allow 3 dimensional movement.

Limits to Quantum Computing

        It is unlikely that quantum computers will ever be completely commercially viable and may only ever be used by big corporations using the factorisation algorithm.  This is because the quantum computer is not suited to word processing, design programmes, or any form of internet and email jobs.  However it is suited to large scale cryptography and constructing and efficiently searching large scale computers.  At present it will be difficult to build a quantum computer of any size as the more qubits interacting the harder it is to control and stop the qubits dissipating useful information to the surrounding environment.  There are also technical issues of working on a sub-atomic and single-photon scale.  

...read more.

This student written piece of work is one of many that can be found in our AS and A Level Modern Physics section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related AS and A Level Modern Physics essays

  1. Peer reviewed

    Albert Einstein - The father of modern physics

    4 star(s)

    on a body, this is covered by ?general relativity? (but I thought I would just add this on anyway because it?s cool), this leads to some very interesting theoretical physics surrounding black holes, which exert such a powerful force of attraction that light itself cannot escape it?s grasp.

  2. How temperature affects the viscosity of honey

    honey around it, this caused extra drag slowing the ball bearing down and giving inaccurate readings. This problem could be easily solved however using a small piece of card just big enough to cover and rest on the top of the measuring cylinder.

  1. The Life and Influences of Albert Einstein

    Another study Einstein performed was the relationship between mass and energy. He discovered that the two are equivalent (Swisher p.41). However, in the past, "scientists had thought energy and mass were separate and had developed separate laws for each. With this new perspective, Einstein reasoned that if a body, a

  2. Prove or conversely disprove the inverse square law.

    of 103 meters, so I did experiments involving visible light and Gamma radiation. Both members of the electro-magnetic spectrum, gamma being present at the far end of the spectrum with extremely high frequency of anything from 1019 to 1021 Hz and a low wavelength of anything from 10-11 to 10-13 metres.

  1. Free essay

    The development of the modern concept of the atom, the size and nature of ...

    These cathode-ray particles are now known as electrons. Soon after the discovery of electrons the proton was discovered. This led Thomson to conclude that there were an equal number of both particles present in the atom. Twelve years later Lord Ernest Rutherford was experimenting with alpha particles. He shot a stream of them at a piece of gold foil surrounded by zinc-sulfide.

  2. A2 OCR B (Advancing Physics) - Research and Report: Nuclear Fusion as an Energy ...

    However it causes great safety concern; in some severe circumstances radiation can be released from the reactor core putting the surrounding area at risk. There is also the concern of nuclear waste created from nuclear plants as to where to put it.

  1. Quantum Phenomena Observed During Near Absolute Zero Conditions

    For example, if we turn our back on an object, does that object even exist anymore; was it just a part of our imagination, a virtual reality? However, we are not here to discuss about such philosophical subjects, as I mentioned before, there are some special cases where certain objects

  2. Modern Physics - AQA GCE Physics B - Revision Notes

    will be formed ? This is called the second harmonics or the first overtone. * In pipes, the wave medium is usually air and the waves themselves are longitudinal. Displacements rather than pressure are used to represent the standing waves in pipes.

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work