July 2011

Manganites are compounds of manganese oxides which are feature colossal magnetoresistance - and are promising candidates for spintronics applications. Researchers from the University of Colorado discovered that 2D bilayer manganite (a lanthanum strontium manganese oxide) can change its stripes from fluctuating to static and back. Magnatide stripe are regions where where the material’s electrical charges gather and concentrate. Other so-called correlated-electron materials also have stripes, including many high-temperature superconductors having the same crystal structure: arrangements of layers of atoms named for the mineral perovskite.

The results mean that the material can switch from a metallic state (a conductor) to an insulator. This is the first good insight into what happens to the electronic properties of a material when stripes 'fluctuate'. It establishes the existence of a distinct new phase of the material, which the researchers call fluctuating bi-stripes.

Researchers from Cambridge University developed a more efficient way to generate spin current, using the collective motion of spins called spin waves (the wave property of spins). There are a number of different interactions in spin waves and the researchers's idea was to use such spin wave interactions for generating efficient spin currents.

One of the spin wave interactions (called three-magnon splitting) generates spin current 10 times more efficiently than using pre-interacting spin-waves.

Researchers from Japan's Hokkaido University are developing methods for visualizing electron spin states at surfaces on the nanoscale or atomic scale. They are also developing new materials for nano-spintronics using those visualization methods. Here's a video introducing the research currently under way: