The sharp end of research

Scientists at the

(U of A) have created the sharpest ever single atom tip, which could lead to much clearer electron microscope images.

The researchers, working out of the National Research Council's National Institute of Nanotechnology (NINT) at the U of A, used a unique process to make the tungsten tip. They were able to coat peripheral atoms near the peak with nitrogen, making it effectively a one atom-thick, tough, protective paint job.

"That coating has the effect of binding the little pyramid of tungsten atoms in place," said Dr Robert Wolkow, a physics professor at the U of A and co-author on the research paper published in the Journal of Chemical Physics. "Such a pointy pyramid of metal atoms would normally just smudge away spontaneously. It's like a sand pile; you know you can't make it arbitrarily pointy. If you try to pile on more sand, it flows down and makes a more blunt pile. Metal atoms will do the same thing."