Technologies involving quantum physics, chemical and DNA structures or fibre optics and light-waves promise to revolutionise the future of computers.

I thought it would be a good idea to introduce DNA and Quantum computers to the StarTech Readers to start with and come with others next time as the revolution continues.

DNA computer
DNA computer uses DNA and molecular biology, instead of the traditional silicon-based computer technologies and uses DNA (deoxyribonucleic acids) to store information and perform complex calculations.

In 1994, University of Southern California computer scientist Leonard Adelman introduced the idea of using DNA to solve complex mathematical problems.

Adleman is often called the inventor of DNA computers. His article in a 1994 issue of the journal Science outlined how to use DNA to solve a well-known mathematical problem, called the directed Hamilton Path problem, also known as the 'traveling salesman' problem.

On April 28, 2004, Ehud Shapiro, Yaakov Benenson, Binyamin Gil, Uri Ben-Dor, and Rivka Adar at the Weizmann Institute announced in the journal Nature that they had constructed a DNA computer. This was coupled with an input and output module and is capable of diagnosing cancerous activity within a cell, and then releasing an anti-cancer drug upon diagnosis.

Researchers at the University of Rochester developed logic gates made of DNA. The Rochester team's DNA logic gates are the first step toward creating a computer that has a structure similar to that of an electronic PC. Instead of using electrical signals to perform logical operations, these DNA logic gates rely on DNA code.

DNA computer fundamentally similar to parallel computing will be able of storing billions of times more data than your personal computer. The prime reason of using DNA computers to solve complex problems is that different possible solutions are created all at once. This is known as parallel processing. Humans and most electronic computers must attempt to solve the problem one process at a time (linear processing). DNA itself provides the added benefits of being a cheap, energy-efficient resource.

DNA computers will overcome technical limitations that exist in silicon-based microprocessors. Microprocessors made of silicon will eventually reach their limits of speed and miniaturisation. Silicon microprocessors dominate the computing the world for more than 40 years.

According to the Moore's Law, the number of electronic devices put on a microprocessor has doubled every 18 months. Moore's Law is named after Intel founder Gordon Moore, who predicted in 1965 that microprocessors would double in complexity every two years. Many have predicted that Moore's Law will soon reach its end, because of the physical speed and miniaturisation limitations of silicon microprocessors.

DNA computer is not based on Moore's Law. As a result, dramatic improvement is possible regarding speed and capacity. One pound of DNA has the capacity to store more information than all the electronic computers ever built; and the computing power of a teardrop-sized DNA computer, using the DNA logic gates, will be more powerful than the world's most powerful supercomputer.

More than 10 trillion DNA molecules can fit into an area no larger than 1 cubic centimetre (0.06 cubic inches). With this small amount of DNA, a computer would be able to hold 10 terabytes of data, and perform 10 trillion calculations at a time. By adding more DNA, more calculations could be performed.

Quantum computer
Paul Benioff, a physicist at the Argonne National Laboratory first introduced the concept of quantum computing. He is credited with first applying quantum theory to computers in 1981. In 1999, the feasibility of such a computer was demonstrated by a collaboration of scientists at MIT, the University of California at Berkeley and Stanford University, which used a technique similar to MRI scans in hospitals. The computation that was accomplished was an ingenious search algorithm devised by Lov K. Grover of Bell Laboratories.

A quantum computer is any device for computation that makes direct use of distinctively quantum mechanisum phenomena, such as superposition and entanglement, to perform operations on data. Nowadays computer we are using is based on two binary states such as 0 and 1. Quantum computers aren't limited to two states; they encode information as quantum bits, or qubits. A qubit can be a 1 or a 0, or it can exist in a superposition that is simultaneously both 1 and 0 or somewhere in between. Qubits represent atoms that are working together to act as computer memory and a processor. Because a quantum computer can contain these multiple states simultaneously, it has the potential to be millions of times more powerful than today's most powerful supercomputers.

It has anticipated that, if large-scale quantum computers can be built, they will be able to solve certain problems asymptotically faster than any classical computer. Quantum computers are different from other computers such as DNA computers and computers based on transistors, even though these may ultimately use some kind of quantum mechanical effect (for example covalent bonds).

Some computing architectures such as optical computers may use classical superposition of electromagnetic waves, but without some specifically quantum mechanical resource such as entanglement, they do not share the potential for computational speed-up of quantum computers.

There are several success stories in the history of quantum computing and some of them are presented below:

* In August 2000, researchers at IBM-Almaden Research Centre developed the most advanced quantum computer developed to date. The 5-qubit quantum computer was designed to allow the nuclei of five fluorine atoms to interact with each other as qubits, be programmed by radio frequency pulses and be detected by nuclear magnetic resonance (NMR) instruments similar to those used in hospitals. Led by Dr. Isaac Chuang, the IBM team was able to solve in one step a mathematical problem that would take conventional computers repeated cycles. The problem, called order finding, involves finding the period of a particular function, a typical aspect of many mathematical problems involved in cryptography.

* In March 2000, scientists at Los Alamos National Laboratory announced the development of a 7-qubit-quantum computer within a single drop of liquid. The quantum computer uses NMR to manipulate particles in the atomic nuclei of molecules of trans-crotonic acid, a simple fluid consisting of molecules made up of six hydrogen and four carbon atoms. The NMR is used to apply electromagnetic pulses, which force the particles to line up. These particles in positions parallel or counter to the magnetic field allowing the quantum computer to mimic the information encoding of bits in digital computers.

* In 1998, Los Alamos and MIT researchers managed to spread a single qubit across three nuclear spins in each molecule of a liquid solution of alanine or trichloroethylene molecules. Spreading out the qubit made it harder to corrupt, allowing researchers to use entanglement to study interactions between states as an indirect method for analysing the quantum information.

The technologies I discussed above are not available for widespread use yet. But it is apparent to us that, in near future if these technologies become available for practical use it will bring drastic changes in our life.

References: wikipedia.com, howstuffworks.com