From the July 2004 Scientific American Magazine | 0 comments

Magnetic Field Nanosensors ( Preview )

Tiny devices that take advantage of a recently discovered physical effect called extraordinary magnetoresistance could be used in blazingly fast computer disk drives with huge capacities and in dozens of other applications involving the sensing of magnetic fields

By Stuart A. Solin

More from the Magazine

July
2004 Issue
Insights Doom and Gloom by 2100
Staking Claims If It's Broke, Fix It
Antigravity Einstein's Parrot
Buy the Digital Edition

It often happens in science that research focused on one phenomenon results in the unexpected discovery of a new effect that is much more exciting and important. In 1995 a case of this serendipity occurred with my research group, then at the NEC Research Institute in Princeton, N.J.

We were studying the properties of a microelectronics structure called a semiconductor superlattice, which consisted of layers of gallium arsenide and gallium aluminum arsenide stacked like a club sandwich. We knew that this superlattice had very interesting electrical properties. In particular, we were investigating how the thickness of the layers determined whether the superlattice behaved as a metal, with low electrical resistance, or as an insulator, with high resistance. We immersed the system in a magnetic field, a procedure that enabled us to study dynamical processes involving the electrons in the superlattice.

Already a Digital subscriber? Sign-in Now
If your institution has site license access, enter here.

Read Comments (0) | Post a comment

Discuss This Article

Click here to submit your comment.

VIEW:



	Email:
	Name:
	Address:
	Address 2:
	City:
	State:

Subscription Center

Editor's Pick

Adapting to the Freshwater CrisisForward-thinking experts are getting a better handle on the growing global water shortage and coming up with innovative approaches to ensuring the security, safety and sustainability of this resource