Washington: Coming soon is a Magnetic computer which may use far less energy, say scientists.

A team at the University of California, which is developing such computers, claims that the future machines will rely on magnetic microprocessors which consume the least amount of energy allowed by the laws of physics.

Today's silicon-based microprocessor chips rely on electric currents, or moving electrons, that generate a lot of waste heat.

But microprocessors employing nanometer-sized bar magnets -- like tiny refrigerator magnets -- for memory, logic and switching operations theoretically would require no moving electrons, say the scientists.

Such chips would dissipate only 18 millielectron volts of energy per operation at room temperature; the minimum allowed by the second law of thermodynamics and called the Landauer limit. That's one million times less energy per operation than consumed by today's computers.

Brian Lambson, who led the team, said: "Today, computers run on electricity, by moving electrons around a circuit, you can process information. A magnetic computer, on the other hand, doesn't involve any moving electrons.

"You store and process information using magnets, and if you make these magnets really small, you can basically pack them very close together so that they interact with one another. This is how we are able to do computations, have memory and conduct all the functions of a computer." Lambson is working with Jeffrey Bokor, UC Berkeley professor of electrical engineering and computer sciences, to develop magnetic computers.

"In principle, one could, I think, build real circuits that would operate right at the Landauer limit. Even if we could get within one order of magnitude, a factor of 10, of the Landauer limit, it would represent a huge reduction in energy consumption for electronics. It would be absolutely revolutionary," said Prof Bokor.

"The magnetic technology we are working on looks very interesting for ultra low power uses. We are trying to figure out how to make it more competitive in speed, performance and reliability. We need to guarantee that it gets the right answer every single time with a very, very, very high degree of reliability," he added.

The findings have been published in the 'Physical Review Letters' journal.