New Technique Helps Control Direction of Magnetic Waves
30 January 2014
A team of US scientists has come up with a novel technique employing "spin waves" to create and control the direction of fast-moving waves in magnetic fields. The method, described in the journal Nanotechnology, could help improve communication and information processing in computer chips and other electronics.
Spin waves are waves that move in magnetic materials and they resemble the behavior of water waves that occur in the upper layer of the ocean. They also have the ability to transfer energy and information from one place to another and have the potential to enhance the functionality of a broad array of technologies.
It's now possible to transform electromagnetic waves in antennas into spin waves, however they have a long wavelength and their speed of propagation is slow. This is considered a chief limitation to their application since they cannot move over larger distances, unlike short-wavelength spin waves, which require less energy and time to propagate.
In order to overcome this restriction, researchers at New York University's Department of Physics developed nanoscale devices, called "spin torque nano-oscillators" (STNOs), to convert a direct current into spin waves. The scientists demonstrated that these oscillators can be lined in arrays to control the movement of the spin wave energy, similarly to the way antennas are used to navigate electromagnetic waves. The technique, which takes example from the interference of waves and the generation of particular wave propagation patterns by controlling the interference, allows the spin waves to move in specific patterns and directions in a magnetic material.