Electron spin mastered by electrical means

CINCINNATI, Oct. 29 (UPI) -- University of Cincinnati researchers say they have become the first scientists to control an electron's spin orientation using just electrical means.

Transistors have long transmitted data by controlling the movement of the charge of an electron. But scientists say transistors that function by controlling an electron's spin, instead of its charge, would use less energy, generate less heat and operate at higher speeds. That theory resulted in a new field of research called spintronics.

Until now, scientists have attempted to develop spin transistors by incorporating local ferromagnets into device architectures. University of Cincinnati Professor Philippe Debray said a far better and practical way to manipulate the orientation of an electron's spin would be by using purely electrical means, like the switching on and off of an electrical voltage.

And that is what the spintronic researchers led by Debray and Professor Marc Cahay have done.

"We used a quantum point contact -- a short quantum wire -- made from the semiconductor indium arsenide to generate strongly spin-polarized current by tuning the potential confinement of the wire by bias voltages of the gates that create it," Debray said.

The researchers, including graduate students Partha Pratim Das and Krishna Chetry, detailed their complex work in a recent edition of the journal Nature Nanotechnology.