- About Us
- Career Center
- Nano-Social Network
- Nano Consulting
- My Account
Researchers from the University of Alberta in and the National Institute for Nanotechnology in Canada created the sharpest object ever made. The new nano object is tungsten needle tapering down to about the thickness of single atom. The breakthrough might help improve future scanning tunneling microscopes.
The needle, made by Moh'd Rezeq in the group lead by Professor Robert Wolkow at the University of Alberta and the National Institute for Nanotechnology, was initially much blunter. The needle was exposed to pure nitrogen atmosphere which made it thinner and thinner. Tungsten is chemically highly reactive and the nitrogen is used to roughen the tungsten surface. But at the tip, where the electric field created by applying a voltage to the tungsten is at its maximum, N2 molecules are driven away. This process reaches an equilibrium condition in which the point is very sharp.
Furthermore, what N2 is present near the tip helps to stabilize the tungsten against further chemical degradation. Indeed, the resultant needle is stable up to temperatures of 900 degrees Celsius even after 24 hours of exposure to air.
The probe tips used in scanning tunneling microscopes (STMs), even though they produce atomic-resolution pictures of atoms sitting on the top layer of a solid material, are not themselves atomically thin. Rather their radius of curvature at the bottom is typically 10 nm or more.
According to Wolkow says that although a narrower tip will be useful in the construction of STM arrays (you can pack more tips into a small area; and a wide array might even permit movies of atomic motions) the spatial resolution won't improve thereby. The real benefit of the sharp tungsten tips, he believes, will be as superb electron emitters. Being so slender, they would emit electrons in a bright, narrow, stable stream.
The picture shows a field ion microscope (FIM) image of a very sharp tungsten needle. The small round features on the image are individual atoms. The lighter colored elongated features are traces captured as atoms moved during the imaging process (approximately 1 second).
More information can be found on the American Institute of Physics website.
About The Future of Things
The Future of Things (TFOT) is an online magazine dedicated to bringing original content on science, technology, and medicine from around the world. TFOT aims to provide comprehensive, accurate, and high quality coverage of emerging scientific and technological innovations. TFOT's news stories and articles are unique, not only because they include detailed analysis and commentary, but because of the inclusion of in-depth interviews with leading scientists, engineers, and other visionaries who describe their work and offer us a glimpse into our future.
We believe in the importance of bringing science and technology to the awareness of the general public. Good science and technology reporting is an art, but one that requires precision and accuracy. This is exactly why we decided to use "as is" interviews as one of our main journalistic tools. Too often we come across misquoted or misinterpreted scientific and technological information. By letting scientists and engineers describe their work in their own words, we aim to bring a new level of accuracy to science and tech reporting.
For more information, please click here
Copyright © The Future of ThingsIf you have a comment, please Contact us.
Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.
|Related News Press|
Interviews/Book Reviews/Essays/Reports/Podcasts/Journals/White papers
Producing spin-entangled electrons July 2nd, 2015