Quantum computers could one day replace silicon chips, just like the transistor replaced the vacuum tube. But for now, the technology required to develop such a quantum computer is beyond our reach.
Most research in quantum computing is still very theoretical, however there have been several key advances in recent years:-
August 2000 – Researchers at IBM developed, what was claimed to be, the most advanced quantum computer. The 5-qubit quantum computer allowed five nuclei of fluorine atoms to interact with each other as “quantum bits” (qubits). It was “programmed” by radio frequency pulses and detected by nuclear magnetic resonance instruments. Using this, the research team were able to solve in one step, a mathematical problem, which would take a conventional computer several cycles.
March 2000 – A 7-qubit quantum computer with a single drop of liquid was developed. Again NMR is used, but this time to manipulate particles in the atomic nuclei of molecules of trans-crotonic acid (this is a simple fluid consisting of molecules made up of six hydrogens and four carbons). The NMR applies electromagnetic pulses to the fluid, which forces the particles to line up. These particles will be in a position either parallel with or counter to the magnetic field, this is analogous to the information-encoding of “bits” of data in conventional digital computers.
Though scientists and engineers have demonstrated a number of small-scale quantum computers, developers face several profound difficulties in building a commercially viable solution.
The most pressing problem is that it’s difficult to hold a single ion in a steady state while you observe its manipulated energy levels and spin directions. At present this can only be achieved by cooling the ions to a point very hear absolute zero, using lasers.
As is the case with DNA-Computers it is unlikely that quantum computers will replace the desktop PC you are using now. If functional quantum computers can be built, they will be valuable in factoring large numbers, and so will find uses in large-scale cryptography, modelling and indexing of very large databases.
