PORTLAND, Ore. Hole-rich semiconductors like gallium arsenide could enable future spintronic devices which store information on magnetic atoms inserted into their crystalline lattice.
But the current technique of random doping of magnetic atoms makes adding spintronics capabilities a hit-or-miss process. Now researchers claim to have perfected a method of brewing exactly the right molecular arrangement.
Using a scanning tunneling microscope to substitute magnetic (manganese) atoms for individual gallium atoms, Princeton University researchers were able to experiment with different crystalline lattice architectures to optimize spintronic capabilities. Employing a theoretical template hypothesized by University of Iowa professor Michael Flatte, the Princeton researchers confirmed the optimal lattice architecture for a new spintonic material: gallium manganese arsenide.
Results of the spintronics research were published in Thursday's (July 27) edition of Nature magazine.
The researchers claim this is the first time atomic-level manipulations were used to make theoretical predictions about the optimal atomic arrangement in a semiconductor. Moreover, the arrangement was achieved one atom at a time in a crystalline lattice.
"The ability to tailor semiconductors on the atomic scale is the Holy Grail of electronics," said Princeton research leader professor Ali Yazdani. "This method may be the approach that we needed."
GaAs is a candidate for next-generation spintronic devices because of its very high electron mobility compared to silicon. By incorporating magnetic atoms into a gallium manganese arsenide semiconductor, the team said it hopes to separately control spin and charge to enable highly energetic spintronic devices.
They hope to exploit hole-rich GaAs and its high-energy, hole-mediated interactions to create devices that store and process the magnetic-spin orientation of holes.
Researchers at the University of New South Wales (Sydney, Austrailia) recently demonstrated hole-quantum wires that could further enhance communication among future gallium manganese arsenide semiconductors and similar materials.
The spintronics research was funded by the National Science Foundation and the U.S. Army Research Office.