Researchers Put 'Spin' in Silicon

ccellist writes "Physorg.com is reporting on the University of Delaware and Cambridge NanoTech's experiments regarding 'spintronics,' or the ability to use information about electron spin in atoms of silicon to encode information, much like we use information about an electron's charge state in computers today. 'Spintronics' research hopes to usher in a new age of computer speed and performance by measuring and even controlling the angular momentum displayed by all electrons, and using this information to encode data. Researchers for the first time have successfully conducted the spin of electrons in a custom-made silicon chip, a process known as 'spin transport.'"

Comments

Sounds like MRI

[necro81]

After spin injection, electrons in the silicon were then subjected to a magnetic field, which caused their spin direction to "precess" or gyrate (much like gravity's effect on a rotating gyroscope), producing tell-tale oscillations in their measurement.

This sounds like the process used in Magnetic Resonance Imaging. In MRI, they use a BIG magnet to create a very strong magnetic field in a person's body. The main field is usually 1-3 Tesla, depending on the scanner (for reference, Earth's magnetic field is 30-50 microtesla). Then they use smaller magnets to establish a gradient in that main field, and RF pulses to query the spin precession of atoms in the body. In the case of human imaging, I think they focus on the spin precession of a hydrogen nucleus (a proton) in water. In function MRI, they focus on hemoglobin (which contains a little ferromagnetic iron, ya see), to determine where blood is most present. See this for an exhaustive overview of how it works.

Their spintronics methods sound similar, except it's focused on a much smaller volume (a chip instead of a human body), and are tuned to the electrons in doped silicon. Very cool.