Researchers at the US National Institute of Standards and Technology (NIST) say they have found theoretical evidence of a new way to generate high frequency waves. They believe the concept could enable a new generation of wireless technology that would be more secure and resistant to interference.
The team believes an oscillator could harness the spin of electrons to generate microwaves. It predicts that a type of stationary wave called a soliton could be created in a layer of a multilayered magnetic sandwich. Creating the soliton requires that one of the sandwich layers be magnetised perpendicular to the plane of the sandwiched layers. An electric current is then forced through a small channel in the sandwich and, once the soliton is established, the magnetic orientation oscillates at more than 1GHz.
NIST physicist Thomas Silva said: "You might use this effect to create an oscillator in mobile phones that would use less energy than those in use today and the military could use them in secure communications. In theory, you could change the frequency of these devices quite rapidly, making the signals hard for enemies to intercept or jam."
Silva adds the oscillator is predicted to be very stable – its frequency remains constant, even with variations in current. This would also reduce unwanted noise in the system. It also appears to create a steady and strong output signal.
"All we've done at this point is the mathematics, but the equations predict these effects will occur in devices that we think we can realise," Silva said, pointing out the research was inspired by materials that already exist. "We'd like to start looking for experimental evidence that these localised excitations occur, not least because solitons in other materials are hard to generate. If they occur in these devices as our predictions indicate, we might have found a relatively easy way to explore their properties."
