Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Scientist Models Molecular Switch

18.06.2008
Michigan Technological University physicist Ranjit Pati and his team have developed a model to explain the mechanism behind computing’s elusive Holy Grail, the single molecular switch.

If borne out experimentally, his work could help explode Moore’s Law and could revolutionize computing technology.

Moore’s Law predicts that the number of transistors that can be economically placed on an integrated circuit will double about every two years. But by 2020, Moore’s Law is expected to hit a brick wall, as manufacturing costs rise and transistors shrink beyond the reach of the laws of classical physics.

A solution lies in the fabled molecular switch. If molecules could replace the current generation of transistors, you could fit more than a trillion switches onto a centimeter-square chip. In 1999, a team of researchers at Yale University published a description of the first such switch, but scientists have been unable to replicate their discovery or explain how it worked. Now, Pati believes he and his team may have found the mechanism behind the switch.

Applying quantum physics, he and his group developed a computer model of an organometallic molecule firmly bound between two gold electrodes. Then he turned on the juice.

As the laws of physics would suggest, the current increased along with the voltage, until it rose to a miniscule 142 microamps. Then suddenly, and counterintuitively, it dropped, a mysterious phenomenon known as negative differential resistance, or NDR. Pati was astonished at what his analysis of the NDR revealed.

Up until the 142-microamp tipping point, the molecule’s cloud of electrons had been whizzing about the nucleus in equilibrium, like planets orbiting the sun. But under the bombardment of the higher voltage, that steady state fell apart, and the electrons were forced into a different equilibrium, a process known as “quantum phase transition.”

“I never thought this would happen,” Pati said. “I was really excited to see this beautiful result.”

Why is this important? A molecule that can exhibit two different phases when subjected to electric fields has promise as a switch: one phase is the “zero” and the other the “one,” which form the foundation of digital electronics.

Pati is working with other scientists to test the model experimentally. His results appear in the article “Origin of Negative Differential Resistance in a Strongly Coupled Single Molecule-metal Junction Device,” published June 16 in Physical Review Letters. The other coauthors are Mike McClain, an undergraduate from Michigan Tech; and Anirban Bandyopadhyay, of the National Institute for Materials Science, Japan. The work of Pati’s team was financed by a five-year, $400,000 Faculty Early Career Development Program award he received from the National Science Foundation.

Marcia Goodrich | newswise
Further information:
http://link.aps.org/abstract/PRL/v100/e246801
http://www.mtu.edu

More articles from Physics and Astronomy:

nachricht Spintronics: Researchers show how to make non-magnetic materials magnetic
06.08.2020 | Martin-Luther-Universität Halle-Wittenberg

nachricht Manifestation of quantum distance in flat band materials
05.08.2020 | Institute for Basic Science

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: ScanCut project completed: laser cutting enables more intricate plug connector designs

Scientists at the Fraunhofer Institute for Laser Technology ILT have come up with a striking new addition to contact stamping technologies in the ERDF research project ScanCut. In collaboration with industry partners from North Rhine-Westphalia, the Aachen-based team of researchers developed a hybrid manufacturing process for the laser cutting of thin-walled metal strips. This new process makes it possible to fabricate even the tiniest details of contact parts in an eco-friendly, high-precision and efficient manner.

Plug connectors are tiny and, at first glance, unremarkable – yet modern vehicles would be unable to function without them. Several thousand plug connectors...

Im Focus: New Strategy Against Osteoporosis

An international research team has found a new approach that may be able to reduce bone loss in osteoporosis and maintain bone health.

Osteoporosis is the most common age-related bone disease which affects hundreds of millions of individuals worldwide. It is estimated that one in three women...

Im Focus: AI & single-cell genomics

New software predicts cell fate

Traditional single-cell sequencing methods help to reveal insights about cellular differences and functions - but they do this with static snapshots only...

Im Focus: TU Graz Researchers synthesize nanoparticles tailored for special applications

“Core-shell” clusters pave the way for new efficient nanomaterials that make catalysts, magnetic and laser sensors or measuring devices for detecting electromagnetic radiation more efficient.

Whether in innovative high-tech materials, more powerful computer chips, pharmaceuticals or in the field of renewable energies, nanoparticles – smallest...

Im Focus: Tailored light inspired by nature

An international research team with Prof. Cornelia Denz from the Institute of Applied Physics at the University of Münster develop for the first time light fields using caustics that do not change during propagation. With the new method, the physicists cleverly exploit light structures that can be seen in rainbows or when light is transmitted through drinking glasses.

Modern applications as high resolution microsopy or micro- or nanoscale material processing require customized laser beams that do not change during...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

“Conference on Laser Polishing – LaP 2020”: The final touches for surfaces

23.07.2020 | Event News

Conference radar for cybersecurity

21.07.2020 | Event News

Contact Tracing Apps against COVID-19: German National Academy Leopoldina hosts international virtual panel discussion

07.07.2020 | Event News

 
Latest News

Rare Earth Elements in Norwegian Fjords?

06.08.2020 | Earth Sciences

Anode material for safe batteries with a long cycle life

06.08.2020 | Power and Electrical Engineering

Turning carbon dioxide into liquid fuel

06.08.2020 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>