February 2012

Researchers with the U.S. DOE's Berkeley Lab in collaboration with scientist from University of Notre Dame have determined the origin of the charge-carriers responsible for the ferromagnetic properties that make gallium manganese arsenide such a hot commodity for spintronic devices.

The study showed that the holes (positively-charged energy spaces) in gallium manganese arsenide that control the Curie temperature, the temperature at which magnetism is lost, are located in an impurity energy band rather than a valence energy band, as many scientists have argued. This finding opens the possibility of fabricating gallium manganese arsenide so as to expand the width and occupation of the impurity band and thereby boost the Curie temperature to improve spintronic potential.

Here's an nice video introducing the NSF Center for Molecular Spintronics at North Carolina State University:

Researchers have discovered a new wide class of topological insulators (materials that are insulators in the bulk but conductors at the surface) that have very promising properties. These new TIs may enable tuning both electronic and spin (that is, magnetic) properties by using different compounds and confirms the possibility to grow topological insulators with deep-laying, self-protecting and, thus, technologically relevant conducting states. This may have applications in spintronics and quantum computation.