May the force be with the atomic probe

December 21, 2012
May the force be with the atomic probe

New models suggest devising means of probing a surface at a sub-micrometric level as this will help us understand how electrons' diffusion affects long-range attractive forces.

Elad Eizner from Ben Gurion University, Israel, and colleagues created models to study the affecting atoms located at a wide range of distances from a surface, in the hundreds of nanometers range. Their results, about to be published in European Physical Journal D, show that these forces depend on electron diffusion, regardless of whether the surface is conducting or not. Ultimately, these findings could contribute to designing minimally invasive surface probes.

Bombarding a surface with atoms helps us understand the distribution of its electrons and the structural arrangement of the . The authors focused on understanding how a long-range force- referred to as the van der Waals-Casimir-Polder (vdW-CP) force - present between an atom and a surface allow us to distinguish surface characteristics on the basis of their conductivity.

A key factor in understanding the behaviour of the force, they realised, is the size of the electron cloud surrounding an impurity charge in the system. The latter depends both on the electrons' conductivity and their capability to diffuse in and along the surface.

They devised one model for the diffusion of the in the bulk of the material and another one in the near-surface region. They tested their models on both conducting and non-conducting surfaces. They were thus able to explain why the atom-surface force shows a continuous transition in terms of conductivity between both types of surfaces.

For distances comparable to the size of the spread, the strength of the vdW-CP attraction force, they found, can help distinguish between bulk and surface electrons diffusion. It could therefore be used as a probe. Potential applications exist, for example, in quantum computer hardware architectures focusing on the interface between different carriers of quantum bits of information.

Explore further: Organic Molecules Stay on Top

More information: E.Eizner, B. Horovitz, and C. Henkel (2012), Van der Waals-Casimir-Polder interaction of an atom with a composite surface, European Physical Journal D, DOI: 10.1140/epjd/e2012-30294-x

Related Stories

Organic Molecules Stay on Top

November 19, 2007

The van der Waals force, a weak attractive force, is solely responsible for binding certain organic molecules to metallic surfaces. In a model for organic devices, it is this force alone that binds an organic film to a metallic ...

Physicists take new look at the atom

January 17, 2011

(PhysOrg.com) -- University of Arizona physicists have discovered a new way to measure how single atoms interact with a surface. Their findings help develop nanotechnology and test new theories about the internal structure ...

Resolving water's electrical properties

May 18, 2011

An old confusion about the electrical properties of water's surface has ended, thanks to scientists at Pacific Northwest and Lawrence Livermore National Laboratories. The conflict arose because two types of measurements gave ...

Electric charge disorder: A key to biological order?

April 30, 2012

Theoretical physicist Ali Naji from the IPM in Tehran and the University of Cambridge, UK, and his colleagues have shown how small random patches of disordered, frozen electric charges can make a difference when they are ...

Recommended for you

Electrical circuit made of gel can repair itself

August 25, 2015

(Phys.org)—Scientists have fabricated a flexible electrical circuit that, when cut into two pieces, can repair itself and fully restore its original conductivity. The circuit is made of a new gel that possesses a combination ...

Biological tools create nerve-like polymer network

August 24, 2015

Using a succession of biological mechanisms, Sandia National Laboratories researchers have created linkages of polymer nanotubes that resemble the structure of a nerve, with many out-thrust filaments poised to gather or send ...

2 comments

Adjust slider to filter visible comments by rank

Display comments: newest first

spaceagesoup
not rated yet Dec 21, 2012
where's the paper ? link dead
TootiCat
not rated yet Dec 27, 2012
The link works fine now.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.