Navigation Links
A new class of electron interactions in quantum systems

Physicists at the University of New South Wales have observed a new kind of interaction that can arise between electrons in a single-atom silicon transistor.

The findings, to be published this week in the journal Physical Review Letters, offer a more complete understanding of the mechanisms for electron transport in nanostructures at the atomic level.

"We have been able to study some of the most complicated transport mechanisms that can arise up to the single atom level," says lead author Dr Giuseppe C. Tettamanzi, from the School of Physics at UNSW.

The results contained in this study open the door for new quantum electronic schemes inwhich it is the orbital nature of the electrons and not their spin or their charge that plays a major role, he says.

The study, in collaboration with scientists from the ICMM in Madrid and the Kavli Institute in The Netherlands, describes how a single electron bound to a dopant atom in a silicon matrix can interact with many electrons throughout the transistor.

In these geometries, electron-electron interactions can be dominated by something called the Kondo effect. Conventionally, this arises from the spin degree of freedom, which represents an angular momentum intrinsic to each electron and is always in the up or in the down state.

However, researchers also observed that similar interactions could arise through the orbital degree of freedom of the electron. This describes the wave-like function of an electron and can be used to help determine an electrons' probable location around the atom's nucleus.

Importantly, by applying a strong magnetic field, the researchers were able to tune thiseffect to eliminate the spin-spin interactions while preserving the orbital-orbital interactions.

"By tuning the effect in two different symmetries of the fundamental state of the systemwe have observed a symmetry crossover identical to those seen in high-energy physics," says Tettamanzi.

"In our case this crossover was observed simply by using a semiconductor device which is not too different from the transistor you use daily to send your emails."

Tettamanzi, who was recently awarded a prestigious ARC Discovery Early Career Researcher Award fellowship, will now investigate another transport mechanism that can arise in quantum dots and single atom transistors called "quantised charge pumping".

The idea here is to create a current flowing through a nanostructure without applying a voltage between the leads, but by applying varying potentials at one or more gates of the transistor, in an apparent violation of Ohm's law.


Contact: Giuseppe Tettamanzi
University of New South Wales

Related biology technology :

1. LoneStar Heart Acquires Worldwide Exclusive Rights to New Class of Small Molecules That May Lead to New Treatments for Diabetes
2. Omeros Announces it has Unlocked 30 Percent of Class A Orphan GPCRs
3. Veracyte Announces Medicare Coverage for Its Afirma® Gene Expression Classifier for Improved Thyroid Nodule Diagnosis
4. StemCyte Adds World Class Talent to its North America and Global Operations
5. Omeros Announces It Has Unlocked Over 20 Percent of Class A Orphan GPCRs
6. Dual-acting class of antimalarial compounds discovered with potential to prevent and treat malaria
7. New Class of Stem Cell-Like Cells Discovered in Spinal Cord Offers Possibilities for Spinal Cord Repair
8. New Data Suggest Veracytes Afirma® Gene Expression Classifier Cost-Effectively Resolves Inconclusive Thyroid Nodule FNA Biopsy Results
9. SynCo Bio Partners Expands the Class A Zone in its Aseptic Filling Facility
10. HCCS Releases Classroom Management Features for Low Cost Learning Management System
11. Ohios Bioscience Industry Thrives With World-Class Industry Collaboration
Post Your Comments:
(Date:6/24/2016)... ... ... Researchers at the Universita Politecnica delle Marche in Ancona combed medical journal articles ... findings are the subject of a new article on the Surviving Mesothelioma website. ... blood, lung fluid or tissue of mesothelioma patients that can help point doctors to ...
(Date:6/23/2016)... ... June 23, 2016 , ... UAS ... the launch of their brand, UP4™ Probiotics, into Target stores nationwide. The company, ... proud to add Target to its list of well-respected retailers. This list includes ...
(Date:6/23/2016)... June 23, 2016 /PRNewswire/ - FACIT has announced ... biotechnology company, Propellon Therapeutics Inc. ("Propellon" ... commercialization of a portfolio of first-in-class WDR5 inhibitors ... such as WDR5 represent an exciting class of ... precision medicine for cancer patients. Substantial advances have ...
(Date:6/23/2016)... HOUSTON , June 23, 2016 ... agreement with the Cy-Fair Sports Association to serve ... of the agreement, Houston Methodist Willowbrook will provide ... education and connectivity with association coaches, volunteers, athletes ... partner with the Cy-Fair Sports Association and to ...
Breaking Biology Technology:
(Date:4/28/2016)... , April 28, 2016 First quarter ... (139.9), up 966% compared with the first quarter of 2015 ... totaled SEK 589.1 M (loss: 18.8) and the operating margin was ... (loss: 0.32) Cash flow from operations was SEK 249.9 ... 2016 revenue guidance is unchanged, SEK 7,000-8,500 M. The ...
(Date:4/15/2016)... , April 15, 2016  A new partnership ... more accurate underwriting decisions in a fraction of ... competitively priced and high-value life insurance policies to ... With Force Diagnostics, rapid testing (A1C, ... data readings (blood pressure, weight, pulse, BMI, and ...
(Date:3/31/2016)... BOCA RATON, Florida , March 31, 2016 /PRNewswire/ ... LEGX ) ("LegacyXChange" or the "Company") ... presentation for potential users of its soon to be ... The video ( ) will also ... by the use of DNA technology to an industry ...
Breaking Biology News(10 mins):