Nanoscale magnetic waves could replace microwave technology
By Ben Coxworth
September 8, 2011
The microwave technology used in applications such as mobile phones and wireless networks may be on its way to being replaced - with parts that are smaller, less expensive, and that consume less resources. Instead of microwaves, devices of the future may use spin waves, which are nanoscale magnetic waves. For almost ten years, it has been theorized that spin waves could be propagated using magnetic nanocontacts. Recently, scientists from the University of Gothenburg and the Royal Institute of Technology, Sweden, became the first people to demonstrate that the theory meshes with observable phenomena.
The study began two years ago, when the researchers started construction of their magnetic nanocontacts. Using one of the world's three advanced spin wave microscopes, at the University of Perugia in Italy, they were able to visualize the movement of the spin waves created by those contacts. The waves rippled out through a thin film of nickel-iron alloy, which was three nanometers thick.
According to the scientists, these results have opened the way for a new field of research known as "magnonics," that utilizes spin waves. The technology could reportedly be integrated into traditional microwave-based electronic circuits, although the added magnonic components would be much better suited to miniaturization than their present-day microwave counterparts.
"I believe that our results will signal the start of a rapid development of magnonic components and circuits," said the University of Gothenburg's Prof. Johan Akerman. "What is particularly exciting is that these components are powered by simple direct current, which is then converted into spin waves in the microwave region. The frequency of these waves can be directly controlled by the current. This will make completely new functions possible."
The research was recently published in the journal Nature Nanotechnology.
Below is a video depicting a simulation of six wave-producing magnetic nanocontacts placed in a circle, illustrating how the contacts can be placed in any pattern.