A race on an infinitesimally small scale

Welcome to the nanoworld. The NanoCar race takes place on a very small scale, that of molecules and atoms: the nano scale...as in nanometer! A nanometer is a billionth of a meter, or 0.000000001 meters or 10 ^-9 m. In short, it is:

• 500,000 times thinner then a line drawn by a ball point pen;
• 30,000 times thinner than the width of a hair;
• 100 times smaller than a DNA molecule;
• 4 atoms of silicon lined up next to one another.

The 4-STM Microscope : How is it possible to see on the nano scale?

A very powerful microscope is necessary to observe molecules and atoms: the scanning tunneling microscope (STM) makes this possible, and it is also responsible for propelling the NanoCars.

© Cyril FRESILLON/CEMES/CNRS Photothèque

The scanning tunneling microscope was invented in 1981 by Gerd Binnig and Heinrich Rohrer, and earned them the Nobel Prize in Physics in 1986. The tunnel effect is a phenomenon in quantum mechanics: using a tip and an electric current, the microscope will use this phenomenon to determine the electric conductance between the tip and the surface, in other words the amount of current that is passing through. Screening provides an electronic map of the surface and of each atom or molecule placed on it.

The "tunnel effect" occurs on the atomic and subatomic scale, and thus cannot be explained by conventional mechanics...When the tip of the scanning tunneling microscope comes within 1 nm of the surface, the electrons "hesitate" to stay, on the tip and can be transferred onto the surface. This is known as the tunnel effect.

A set of novel scanning tunneling microscopes in Toulouse

At the CNRS's Centre d'élaboration de matériaux et d'études structurales (CEMES) in Toulouse, it is the one of a kind STM microscope that makes the race possible: the equivalent of four scanning tunneling microscopes, this device is the only one able to simultaneously and independently map four sections of the track in real time, thanks to its four tungsten tips.

STM images of the Nanocars

However difficult to imagine, the resolution of the images obtained is 2 picometers, or 10!^-12 m !

Seeing and controlling NanoCars

Seeing four sections of the race is not the only achievement, as the tips of the microscope give the supply the four NanoCars with the energy they need to move forward. Each of the four teams will be provided with a control screen to guide and control their car.

© Hubert RAGUET CEMES CNRS Photothèque