Wednesday, September 22, 2010

QUANTUM COMPUTERS

Since the invention of integrated circuits, there has been a tremendous increase in chip density, drastic decrease in chip size, followed by reduction in power consumption. But how far this could go further, so as to maintain Moore’s law?  This is the question which shook the semiconductor industry and the leading scientists in this field. Today we are in a stage where semiconductor industries are reaching their limits and getting saturated. And now various studies and researches unanimously point to very unique solution - The Quantum Computer. Quantum computers will be the next greatest leap to satisfy humans ever found quest for better computing speed, power and accuracy. In addition quantum communication is yet another break through in wireless communication.

Quantum computers are future computers which work on the principle of quantum physics. At present in electronic computers and devices, the fundamental component is transistor and associated circuits. But in quantum computers, the fundamental components are molecules, atoms and even electrons. Here the classical physics fails to explain the extra ordinary phenomenon. But quantum physics is well capable of it to some extend.

In electronic computers, fundamental unit of storage is bit. It can posses two values – 0 or1 (high or low, ON/OFF…..etc). At a particular instant of time a bit could attain only one state. In quantum computers bits are replaced by qbits. A qbit could attain a value, either 1 or 0 or both at a particular instant of time. The value of qbit depends on how we read it. It is this remarkable feature which lifts up quantum computers to the top of everything. It is this unique property which tremendously increases its computing power as well as efficiency.

Bits are represented either as a presence or absence of charge in capacitors or as whether the transistor is ON/OFF etc. But a qbit can be represented as the direction of spin of electrons in an atom. For example a clockwise spin would represent a qbit=1 and an anti-clockwise spin would represent a qbit=0.

Consider a group of n bits. It could represent 2^n states. But only one state at a particular instant of time. Thus it is deterministic. Regardless of the way we read this, its state remains same for all the connected parts in a circuit. But in the case qbits the situation is different. Qbits could represent 2^n states. In addition it could attain 2^n states simultaneously at a particular instant of time. In other words, the state of qbit depends on how we read it. Thus if could develop sufficient technology for reading and writing qbits, the result would be an increase in computational power by a factor of 2^n. Thus even a minimum level 12-qbit quantum computer would far exceed present day’s best super computer.

The use of quantum materials in communication is yet another upcoming revolution. It is proved that the state of two materials which have a quantum relation remains same, regardless of their separation. Thus a change in state of one of the quantum related material would make a corresponding change in its counter part. Even if these are kept in various solar systems, these materials will track each other’s changes instantaneously. If we could exploit these materials for our communication, the result will be a better, faster and secure communication with almost unlimited range. Though the above mentioned ideas are theoretically proved, the technology is still far below to put these things in to practical. But the higher rate in development in this field gives us a better hope.

Recently a Chinese researcher succeeds in testing quantum communication up to a distance of 16km. Also major powers of computing industry are pushing their R &D towards quantum computers. A very few 8-qbit and recently 12-qbit quantum computers are developed. But none of these are up to the mark and were not standardized.

We could certainly dream about an era of quantum computers. But at present if some one succeds in  building a quantum computer, the data on the networks, internet etc are no more secure. Because the quantum computers could decode even the best encryption algorithms within a fraction of a second !!!!!!!!!!   
  
   

0 comments:

Post a Comment

Twitter Delicious Facebook Digg Stumbleupon Favorites More

 
Design by Free WordPress Themes | Bloggerized by Lasantha - Premium Blogger Themes | coupon codes