Long stripes
of magnetic domains appear in the magnetic material on one side of a tiny channel.
Initial applications based
on magnetic domain walls have been developed and are already in use in sensor technology.
But due to the ferromagnetic interaction between them, they can also stick together forming an elementary
mobile magnetic domain with about the same probability.
To speed up these processes, researchers have recently started to explore the use of ultrashort laser pulses that can
switch magnetic domains in solid - state materials.
Until now it hasn't been obvious how one could
control magnetic domain walls reversibly and predictably using electric fields.
«Even if this particular material will probably not be used because of the low temperatures and
strong magnetic domains required, our experiments show what this kind of control could, in principle, look like,» adds Simon Gerber, first author of the publication.
Small magnetic domain wall structures in nanowires can be used to store information and, for example, can be used as angle sensors.
One possibility: time is just another spatial dimension except at the beginning of space and time This is perhaps like formation of an ice crystal or alignment
of magnetic domains, a phase change in which time becomes timelike.
Concepts for information storage and logical processing based
on magnetic domain walls have great potential for implementation in future information and communications technologies.»
The MPQ team has now succeeded to observe these most elementary
mobile magnetic domains, the two - magnon states, directly and to resolve their dynamics with time - resolved measurements.
The magnetic coercivity, the resistance to change in the orientation of
the magnetic domain structure, for nickel (Ni) was shown to strongly depend on the crystal structure of the underlying oxide (vanadium oxide).
Magnetic Domain - Wall Racetrack Memory.
A magnetic domain wall forms in a magnetic wire and separates regions where the magnetisation points in opposite directions.
In the course of their research into the use of
magnetic domain walls (local regions of magnetic «charge» usually driven by magnetic fields) to increase our capacity for information storage and logical processing, physicists at the University of Nottingham have discovered a phenomenon which has allowed them to «manipulate» the structure of a magnetic domain wall.
IBM calls dubs it «racetrack memory,» because it uses
magnetic domains to store information in columns of magnetic material (nanoscale «racetracks») arranged on the surface of a silicon wafer.
At Mainz University, the group of Professor Mathias Kläui is studying the properties of
magnetic domains and the dynamics of domains and domain walls in tiny rings on the nanoscale.
As the bar is crushed or bent,
these magnetic domains shift positions with respect to each other and scientists can detect the associated changes in the bar's magnetic field.
Hard drives, for instance, are made by
magnetic domains, and those magnetic domains are about 10 nanometers apart.»
In nanometer - thin magnetic films, such as iron - nickel alloys, the region separating two
magnetic domains or defects can adopt tiny whirlpool - like patterns.
«If you can image the size of the material's
magnetic domains and how they evolve on small length scales, that gives you information about the value and strength of these interactions,» she added.
Results showed that the magnetic squares changed their properties under the effect of SAWs, growing or shrinking
the magnetic domains depending on the phase of the SAW.