Featured Research

from universities, journals, and other organizations

Molecules as circuits? Miniaturization of electronic devices

Date:
January 23, 2014
Source:
Sissa Medialab
Summary:
Silicon-based electronics has certain limits, in the physical sense of the word: this type of circuit can never become “nano” because of the physical laws governing the flow of electrons. This imposes a halt to the process of miniaturization of electronic devices. One of the possible solutions is to use molecules as circuits, but their poor conduction capabilities make them unlikely candidates. There is, however, a possible way around this, which was investigated in a recent article.

Silicon-based electronics has certain limits, in the physical sense of the word: this type of circuit can never become "nano" because of the physical laws governing the flow of electrons. This imposes a halt to the process of miniaturization of electronic devices. One of the possible solutions is to use molecules as circuits, but their poor conduction capabilities make them unlikely candidates. There is, however, a possible way around this, which was investigated in a recent paper published in Proceedings of the National Academy of Sciences (PNAS) by an international research team that includes Ryan Requist, Erio Tosatti and Michele Fabrizio of the International School for Advanced Studies (SISSA) in Trieste.

The Kondo effect, first described last century by the Japanese physicist Jun Kondo, is observed when magnetic impurities, i.e., very few atoms (even only 1 in 1000) of magnetic material such as iron are added to metals like gold or copper. Even molecules like nitric oxide behave like magnetic impurities: when located between metal electrodes they give rise to a Kondo effect. This effect, as the study authors show, could be exploited to change the conductance between the two electrodes. Requist and Tosatti created a computer model of the Kondo effect under these conditions and formulated predictions on the behaviour of the molecules. These were then tested in experiments carried out by the experimental physicists involved in the study.

The results are encouraging: "Our work demonstrates for the first time that we can predict the Kondo effect quantitatively and it offers a theoretical basis for similar calculations with larger and more complex molecules. In the future it might be helpful when searching for the most appropriate molecules for these purposes," commented Requist.

The Kondo effect occurs when the presence of a magnetic atom (an impurity) causes the movement of electrons in a material to behave in a peculiar way.

"Every electron has a mechanical or magnetic rotation moment, termed spin," explains Erio Tosatti. "Kondo is a phenomenon related to the spin of metal electrons when they encounter a magnetic impurity. The free metal electrons cluster around the impurity and "screen it out" so that it can no longer be detected, at least so long as the temperature is sufficiently low." This results in specific properties of the material, for example an increase in electrical resistance.

"Conversely, in conditions involving very small size scales (the tip of a tunnelling electron microscope) such as those used in this study, the result is instead an increase in conductivity," explains Requist.

The research collaboration that carried out the study saw the participation of SISSA, CNR-IOM Democritos, ICTP, the University of Trieste, the University of Technology of Dresden and the French Alternative Energies and Atomic Energy Commission (CEA).


Story Source:

The above story is based on materials provided by Sissa Medialab. Note: Materials may be edited for content and length.


Journal Reference:

  1. R. Requist, S. Modesti, P. P. Baruselli, A. Smogunov, M. Fabrizio, E. Tosatti. Kondo conductance across the smallest spin 1/2 radical molecule. Proceedings of the National Academy of Sciences, 2013; 111 (1): 69 DOI: 10.1073/pnas.1322239111

Cite This Page:

Sissa Medialab. "Molecules as circuits? Miniaturization of electronic devices." ScienceDaily. ScienceDaily, 23 January 2014. <www.sciencedaily.com/releases/2014/01/140123075531.htm>.
Sissa Medialab. (2014, January 23). Molecules as circuits? Miniaturization of electronic devices. ScienceDaily. Retrieved July 24, 2014 from www.sciencedaily.com/releases/2014/01/140123075531.htm
Sissa Medialab. "Molecules as circuits? Miniaturization of electronic devices." ScienceDaily. www.sciencedaily.com/releases/2014/01/140123075531.htm (accessed July 24, 2014).

Share This




More Matter & Energy News

Thursday, July 24, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Robot Parking Valet Creates Stress-Free Travel

Robot Parking Valet Creates Stress-Free Travel

AP (July 23, 2014) 'Ray' the robotic parking valet at Dusseldorf Airport in Germany lets travelers to avoid the hassle of finding a parking spot before heading to the check-in desk. (July 23) Video provided by AP
Powered by NewsLook.com
Boeing Ups Outlook on 52% Profit Jump

Boeing Ups Outlook on 52% Profit Jump

Reuters - Business Video Online (July 23, 2014) Commercial aircraft deliveries rose seven percent at Boeing, prompting the aerospace company to boost full-year profit guidance- though quarterly revenues missed analyst estimates. Bobbi Rebell reports. Video provided by Reuters
Powered by NewsLook.com
Europe's Car Market on the Rebound?

Europe's Car Market on the Rebound?

Reuters - Business Video Online (July 23, 2014) Daimler kicks off a round of second-quarter earnings results from Europe's top carmakers with a healthy set of numbers - prompting hopes that stronger sales in Europe will counter weakness in emerging markets. Hayley Platt reports. Video provided by Reuters
Powered by NewsLook.com
9/11 Commission Members Warn of Terror "fatigue" Among American Public

9/11 Commission Members Warn of Terror "fatigue" Among American Public

Reuters - US Online Video (July 22, 2014) Ten years after releasing its initial report, members of the 9/11 Commission warn of the "waning sense of urgency" in combating terrorists attacks. Mana Rabiee reports. Video provided by Reuters
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins