Magnetic tips sees fine detail, lost data.If you need more memory in your computer, or if you think computer programs that retrieve lost data files and "fix" bad disks work miracles, then you'll really like this new application of scanning tunneling microscopy (STM (Scanning Tunneling Microscope) A microscope that can image down to the atomic level. An STM uses a piezoelectric tube with a tiny sharp tip at the end that is moved within nanometers of the object being sampled. ). Scientists typically use STM to get atomic-scale images of the surfaces of materials. These researchers use a very fine metal tip to scan a surface. Variations in the current created as electrons hop the varying distances between the tip and the surface enable them to map the material's topography. Two years ago, John Moreland and Paul Rice Paul Rice is the founder and CEO of the non-profit organisation Transfair USA. He lived in Nicaragua for 11 years working with local coffee farmers before he returned to the US to found what is now the largest fair trade organisation in the US. of the National Institute of Standards and Technology National Institute of Standards and Technology, governmental agency within the U.S. Dept. of Commerce with the mission of "working with industry to develop and apply technology, measurements, and standards" in the national interest. (NIST (National Institute of Standards & Technology, Washington, DC, www.nist.gov) The standards-defining agency of the U.S. government, formerly the National Bureau of Standards. It is one of three agencies that fall under the Technology Administration (www.technology. ) in Boulder, Colo., reported that they could measure variations in magnetic force across a surface by replacing the standard metal STM tip with a flexible, magnetic one. The new tip allows scientists to see these variations more easily and in much finer detail than they would with other imaging techniques, says physicist Romel D. Gomez. In the Feb. 16 APPLIED PHYSICS LETTERS Applied Physics Letters is a weekly peer-reviewed scientific journal published by the American Institute of Physics devoted to the publication of new experimental and theoretical papers about applications of physics to science, engineering, and modern technology. , Gomez and his colleagues at the University of Maryland University of Maryland can refer to:
"The theory tells you that the image you get is directly the field that you see on the surface," Gomez says. The tip moves closer to or farther from the surface depending on the strength and direction of the surface's magnetic field at any given point. That distance alters the current between the tip and the surface, so the hills and valleys in the resulting image show in submicron detail how the magnetic field changes. "It's a much more sensitive way of reading magnetic domains, which will allow us to have very high-density computers," Gomez adds. A computer stores information on hard disks by creating microscopic patterns of magnetization on the disk. When it erases or writes over data, the computer covers the old magnetization pattern with a new one. Under the magnetic STM tip, this pattern shows up with greater resolution than a computer can read, says Gomez. In addition, the magnetic tip can "read between the lines Between the lines can refer to:
NIST has a patent pending for using this technique to image and alter magnetization patterns on surfaces. |
|
||||||||||||||||||
Printer friendly
Cite/link
Email
Feedback
Reader Opinion