Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Changing the Channel in Nanoelectronics

19.04.2010
New computer simulations may help in the design of efficient molecular wires

Two types of trends can be identified in the length-dependent conductance of molecular wires, according to Chinese scientists.

In an article published online in ChemPhysChem, Jianwei Zhao and colleagues describe different length–conductivity relationships in molecular wires depending on the structures dominating the electron-transport channels. With the aid of computer simulations, the researchers were able to define a quantitative relation between the energy band gaps of different conjugated molecules and the attenuation factor—an important parameter that determines the distance over which charge can be conducted efficiently through a material.

“The new results may be helpful in the design of molecular wires for nanoelectronic applications”, the researchers say.

An important step in the development of electronic devices at the single-molecule level is the understanding of charge transport through individual molecular wires. In the macroscopic world, the resistance of a metallic wire increases linearly with length. But the situation is completely different for nanometer-long molecular wires, which may have diverse molecular structures leading to different electron-transport behaviors.

To address this problem, Zhao and co-workers investigated the length dependence of the conductance through several conjugated organic molecules, thereby identifying two different trends depending on the molecular structure: a single-channel conductance and a multichannel one. The researchers found that in the case of single-channel molecules such as oligothiophene (an organic semiconductor), the conductance decays rapidly with the length, following an exponential law. However, if the molecular wires have multichannels, the decay of conductance shows a different behavior. For example, the conductance of short porphyrin-based chains decays almost linearly with length, making this type of conjugated molecules particularly promising for applications as molecular wires, according to the authors.

The simulations carried out by the Chinese team have also allowed them to find a way to determine the attenuation factor—an important indicator of electron transport through a molecular wire—directly from the energy band gap of the organic compound. The researchers believe that this observation could be of use in reaching one of the ultimate goals in molecular electronics: the design of robust molecular wires with efficient electron transport over long distances.

Author: Jianwei Zhao, Nanjing University (China), http://www.51-stars.com.cn/english/facultylr.asp?fln=ZHAO,Jianwei

Title: The Diversity of Electron-Transport Behaviors of Molecular Junctions: Correlation with the Electron-Transport Pathway

ChemPhysChem 2010, 11, No. 9, Permalink to the article: http://dx.doi.org/10.1002/cssc.201000092

Jianwei Zhao | Wiley-VCH
Further information:
http://www.chemphyschem.org
http://www.51-stars.com.cn/english/facultylr.asp?fln=ZHAO,Jianwei

More articles from Life Sciences:

nachricht Link Discovered between Immune System, Brain Structure and Memory
26.04.2017 | Universität Basel

nachricht Researchers develop eco-friendly, 4-in-1 catalyst
25.04.2017 | Brown University

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

7th International Conference on Crystalline Silicon Photovoltaics in Freiburg on April 3-5, 2017

03.04.2017 | Event News

 
Latest News

Link Discovered between Immune System, Brain Structure and Memory

26.04.2017 | Life Sciences

New survey hints at exotic origin for the Cold Spot

26.04.2017 | Physics and Astronomy

NASA examines newly formed Tropical Depression 3W in 3-D

26.04.2017 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>