PRESS-NEWS.org - Press Release Distribution
PRESS RELEASES DISTRIBUTION

Molecules as circuits

The Kondo effect can improve a molecule's conductivity

2014-01-23
(Press-News.org) Contact information: Federica Sgorbissa
pressroom@sissa.it
0039-040-378-7644
International School of Advanced Studies (SISSA)
Molecules as circuits The Kondo effect can improve a molecule's conductivity 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.

More in detail…

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).


ELSE PRESS RELEASES FROM THIS DATE:

Tracing unique cells with mathematics

2014-01-23
This news release is available in German. Each cell in our body is unique. Even cells of the same tissue type that look identical under the ...

NCCS scientists discover gene regulation is dependent on protein ANP32E

2014-01-23
PUBLIC RELEASE DATE: 23-Jan-2014 [ | E-mail ] var addthis_pub="eurekalert"; var addthis_options = "favorites, delicious, digg, facebook, twitter, google, newsvine, reddit, slashdot, stumbleupon, buzz, more" Share Contact: Ms Rachel Tan Rachel.Tan.C.H@nccs.com.sg 659-754-0842 SingHealth NCCS scientists discover gene regulation is dependent on protein ANP32E Architecture of DNA is maintained by a protein called ANP32E; Cells lacking ANP32E lacked proper chromatin structure; ANP32E's ability to strip histone H2A.Z from DNA can alter gene expression; Findings ...

Cultural connections with Europe found in ancient Jordanian settlement

2014-01-23
Swedish archaeologists in Jordan led by Professor Peter M. Fischer from the University of Gothenburg have excavated a nearly 60-metre long well-preserved building from 1100 B.C. ...

Near error-free wireless detection made possible

2014-01-23
The accuracy and range of radio frequency identification (RFID) systems, which are used in everything from passports to luggage tracking, could be vastly improved thanks to a new system developed by ...

Insulin-producing beta cells from stem cells

2014-01-23
The findings of the scientists of the Institute of Diabetes and Regeneration Research ...

Choose your love

2014-01-23
To test whether female mate choice enhances the health and disease-resistance of offspring, either through immune resistance, tolerance to infection, ...

Mitochondrial ribosome revealed

2014-01-23
The ribosome can be thought of as a decryption device housed within the cell. It is able to decipher the genetic code, which is delivered in the form of messenger ribonucleic acid (mRNA), and translate it into ...

New microscopy technique improves imaging at the atomic scale

2014-01-23
When capturing images at the atomic scale, even tiny movements of the sample can result in skewed or distorted images – and those movements are virtually impossible to prevent. Now microscopy ...

Detecting sickness by smell

2014-01-23
Humans are able to smell sickness in someone whose immune system is highly active within just a few hours of exposure to a toxin, according to new research published in Psychological Science, a journal of the ...

Interventions work to stem freshman drinking

2014-01-23
PROVIDENCE, R.I. [Brown University] -- A new systematic review of data published in more than 40 studies of freshman alcohol interventions finds that there are many effective ways for colleges to mitigate common drinking ...

LAST 30 PRESS RELEASES:

Study unexpectedly finds living in rural, rather than urban environments in first five years of life could be a risk factor for developing type 1 diabetes

Editorial urges deeper focus on heart-lung interactions in pulmonary vascular disease

Five University of Tennessee faculty receive Fulbright Awards

5 advances to protect water sources, availability

OU Scholar awarded Fulbright for Soviet cinema research

Brain might become target of new type 1 diabetes treatments

‘Shore Wars:’ New research aims to resolve coastal conflict between oysters and mangroves, aiding restoration efforts

Why do symptoms linger in some people after an infection? A conversation on post-acute infection syndromes

Study reveals hidden drivers of asthma flare-ups in children

Physicists decode mysterious membrane behavior

New insights about brain receptor may pave way for next-gen mental health drugs

Melanoma ‘sat-nav’ discovery could help curb metastasis

When immune commanders misfire: new insights into rheumatoid arthritis inflammation

SFU researchers develop a new tool that brings blender-like lighting control to any photograph

Pups in tow, Yellowstone-area wolves trek long distances to stay near prey

AI breakthrough unlocks 'new' materials to replace lithium-ion batteries

Making molecules make sense: A regional explanation method reveals structure–property relationships

Partisan hostility, not just policy, drives U.S. protests

The Journal of Nuclear Medicine Ahead-of-Print Tip Sheet: August 1, 2025

Young human blood serum factors show potential to rejuvenate skin through bone marrow

Large language models reshape the future of task planning

Narrower coverage of MS drugs tied to higher relapse risk

Researchers harness AI-powered protein design to enhance T-cell based immunotherapies

Smartphone engagement during school hours among US youths

Online reviews of health care facilities

MS may begin far earlier than previously thought

New AI tool learns to read medical images with far less data

Announcing XPRIZE Healthspan as Tier 5 Sponsor of ARDD 2025

Announcing Immortal Dragons as Tier 4 Sponsor of ARDD 2025

Reporting guideline for chatbot health advice studies

[Press-News.org] Molecules as circuits
The Kondo effect can improve a molecule's conductivity