Basel team secures victory at first nanocar race

The University of Basel team has won the first international nanocar race, which was held on a gold racetrack. The young scientists from the Department of Physics and the Swiss Nanoscience Institute at the University of Basel were the fastest at steering a single molecule along a miniscule gold track measuring around 100 nanometers.

The winners of the nanocar race: Tobias Meier and Dr. Rémy Pawlak together with Christophe Giraud (CNRS Midi-Pyrénées). (Image: Nathalie Lambert / CNRS)

The statistics for the first international nanocar race, which was held in Toulouse from April 28 to 29, do not sound all that spectacular: Within the space of 38 hours, the teams had to guide a single molecule along a gold racetrack measuring around 100 nanometers, and negotiate two bends in the process. But in reality, it wasn’t so easy.

Instead of sitting at the steering wheel, the nanocar drivers sat at a computer that they used to operate a scanning tunneling microscope. Rather than containing lenses that concentrate light, this microscope has a tiny conducting tip, which can be accurately guided over a sample. When the distance between the tip and the sample is small enough, a tiny electrical current flows from the tip to the sample.

Scanning tunneling microscopes are normally used to image minute details – at the scale of single molecules and atoms – of surfaces. For the nanocar race, however, the scientists used the microscope tip to move a single molecule along the racetrack. This is also no trivial feat, as the difference in size between the microscope tip and the molecule is roughly the same as the difference between the Matterhorn and a tennis ball.

From April 28 to 29, the Centre d’Élaboration de Matériaux et d’Études Structurales (CEMES) in Toulouse welcomed scientists from Germany, France, Japan, the USA, Austria, and Switzerland for the world’s first international nanocar race. The event was organized by the Centre National de la Recherche Scientifique (CNRS). Toulouse has one of the only scanning tunneling microscopes in the world that allows four different teams to steer their molecules along the surface at the same time.

The drivers competing for Switzerland were Tobias Meier and Dr Rémy Pawlak from the research group led by Professor Ernst Meyer of the Swiss Nanoscience Institute and the Department of Physics at the University of Basel.

The tip of a scanning tunneling microscope (yellow) gives the nanocar an electrical impulse that moves the molecule. This is how the Swiss team competing in the first international nanocar race steered their nanodragster along a gold surface at a speed of 20 nanometers per hour. (Image: University of Basel, Department of Physics)

Learning while having fun
The race was a major challenge for all the participants. During the many hours they spent preparing, and during the race itself, the teams learned more and more about how to purposefully move molecules, and about which molecules are especially well suited to the task. While other teams chose to race large molecules with movable sections, the Swiss team worked with a very small molecule that had been designed and produced by the team led by Professor Catherine Housecroft from the Department of Chemistry at the University of Basel.

“Our idea was to reduce the friction between the nanocar and the surface so that it could glide over the track like a hovercraft,” explains Dr Rémy Pawlak, driver of the Swiss nanodragster and a postdoc in Ernst Meyer’s group. The plan worked. After just eight hours, the Swiss researchers had reached the finish line of the 100-nanometer-long gold racetrack.

The Austrian-US team was actually even faster, but they raced on a silver surface so their result was not comparable to the five competitors who had raced on a gold track.

“We’re delighted to have won,” says Tobias Meier, a doctoral student in Ernst Meyer’s research group and the second driver in the Swiss team. “Taking part in the race was a lot of fun. Plus, this approach means we keep learning more about how we can control individual molecules. At some stage, these findings will become useful – for instance, in building logical structures like memory chips from individual molecules.

Links

Video:  Swiss Nano Dragster participates in the first nanocar race
YouTube-Channel Nanocar race