Reliable molecular toggle switch developed

March 29, 2017

Nanotechnology constantly allows for new records in miniaturization. Reduction of the dimension of electronic components, however, has physical limits that will be reached soon. Novel materials and components are required. This is where molecular electronics comes in. Scientists of Karlsruhe Institute of Technology (KIT) have now succeeded in developing a molecular toggle switch that does not only remain in the position selected, but can also be flipped as often as desired. This is reported in Nature Communications.

"By replacing conventional silicon-based components, e.g. a switch, by individual molecules, future electronic circuits might be integrated on a space smaller by a factor of 100," Lukas Gerhard of KIT's Institute of Nanotechnology says.

The basic structure of the electromechanical switch consists of a few carbon atoms. Three sulfur atoms form the feet that are fixed to a smooth gold surface. The toggle lever ends in a nitrile group with a nitrogen atom. It is flipped when voltage is applied. The resulting electric field exerts a force on the charge of the nitrogen atom. In this way, contact to a second electrode (here, the gold tip of a scanning tunneling microscope) is established.

The complete switch measures not more than a nanometer. For comparison: The smallest structures used in semiconductor technology are 10 nm in dimension. "Molecular electronics, hence, would be big progress," Gerhard says.

It is not only the size of the switch that is remarkable, but the fact that it works reliably and foreseeably. This means that its operation always leads to a switching state. The contact is either open or closed. So far, implementation of this principle has often failed due to insufficient controllability of electric contacting of individual molecules. For the first time, KIT researchers have now succeeded in opening and closing such a contact between a molecule and a gold tip electrically and mechanically as often as desired, without plastic deformation being caused.

In the opinion of Gerhard, progress in synthetic chemistry has resulted in the possibility of making available a large variety of billions of molecular building blocks of identical atomic design. "Their interconnection, however, requires them to be touched without being damaged." Such a gentle method has now be found and Gerhard considers this to be the decisive novelty.
-end-
This publication is the result of close cooperation between experimental physicists and chemists of KIT's Institute of Nanotechnology and of the University of Basel and theoretical physicists of the University of Konstanz.

Karlsruhe Institute of Technology (KIT) pools its three core tasks of research, higher education, and innovation in a mission. With about 9,300 employees and 25,000 students, KIT is one of the big institutions of research and higher education in natural sciences and engineering in Europe.

KIT - The Research University in the Helmholtz Association

Karlsruher Institut für Technologie (KIT)

Related Nanotechnology Articles from Brightsurf:

Hiring antibodies as nanotechnology builders
Researchers at the University of Rome Tor Vergata recruit antibodies as molecular builders to assemble nanoscale structures made of synthetic DNA.

Nanotechnology delivers hepatitis B vaccine
X-ray imaging shows that nanostructured silica acts as a protective vehicle to deliver intact antigen to the intestine so that it can trigger an immune response.

Want in on nanotechnology? Capitalize on collaborative environments
Patent law experts demonstrate that private-public partnerships lead to promising innovation output measured in patents.

Nanotechnology makes it possible for mice to see in infrared
Mice with vision enhanced by nanotechnology were able to see infrared light as well as visible light, reports a study published Feb.

Healing kidneys with nanotechnology
In new research appearing in the journal Nature Biomedical Engineering, Hao Yan and his colleagues at the University of Wisconsin-Madison and in China describe a new method for treating and preventing Acute Kidney Injury.

A treasure trove for nanotechnology experts
A team from EPFL and NCCR Marvel has identified more than 1,000 materials with a particularly interesting 2-D structure.

Nanotechnology could redefine oral surgery
A trip to the dentist or orthodontist usually instills a sense of dread in most patients, and that's before the exam even begins.

MEDLINE indexes Pharmaceutical Nanotechnology
Pharmaceutical Nanotechnology, an important journal published by Benthm Science, is accepted to be included in MEDLINE.

Nanotechnology and nanopore sequencing
DNA is the hereditary material in our cells and contains the instructions for them to live, behave, grow, and develop.

Nanotechnology: Lighting up ultrathin films
Based on a study of the optical properties of novel ultrathin semiconductors, researchers of Ludwig-Maximilians-Universitaet in Munich have developed a method for rapid and efficient characterization of these materials.

Read More: Nanotechnology News and Nanotechnology Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.