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Primeur weekly 2016-10-24

Focus

EUDAT Project Director Damien Lecarpentier to expand on added value of EUDAT for data storage, the success of the first DI4R Conference and on the importance of Key Performance Indicators for e-infrastructures ...

Quantum computing

Exploring defects in nanoscale devices for possible quantum computing applications ...

Quantum computers: 10-fold boost in stability achieved ...

New 3D wiring technique brings scalable quantum computers closer to reality ...

Focus on Europe

ISC 2017 seeks contributors for Conference programme ...

Middleware

Allinea brings new software performance briefings to SC16 ...

Hardware

Innovative technique for shaping light could solve bandwidth crunch ...

R&D collaboration in integrated electronic systems receives top award ...

UK Met Office installs new HPC system to significantly improve productivity of weather and climate data analysis ...

Fast data sharing with South Korea via Netherlight ...

NSF funds new projects to advance energy-efficient computing ...

Applications

Can we find more benign nanomaterials? ...

Scientists find technique to improve carbon superlattices for quantum electronic devices ...

A new class of materials could realize quantum computers ...

Rhön-Klinikum Hospitals to study how IBM Watson can support doctors in the diagnosis of rare diseases ...

Predicting jellyfish invasions at coastal power stations ...

IBM and Quest Diagnostics launch Watson-powered genomic sequencing service to help physicians bring precision cancer treatments to patients nationwide ...

A new spin on superconductivity ...

Insilico Medicine to present on recent advances in AI at BioData World in Cambridge ...

Unraveling the science behind biomass breakdown ...

T-rays will speed up computer memory by a factor of 1,000 ...

Promise of gene therapy for glaucoma shines bright in award-winning image ...

The Cloud

Amazon Web Services Cloud now available to customers from data centres in Ohio ...

IBM Cloud expands Bluemix ecosystem in China to fuel blockchain and IoT innovation ...

Atos teams with VMware to launch Digital Private Cloud offering ...

DNAstack launches genomics platform to accelerate disease research and precision medicine ...

A new spin on superconductivity


Harvard researchers found a way to transmit spin information through superconducting materials. Credit: WikiCommons.
14 Oct 2016 Cambridge - Researchers from the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS) have made a discovery that could lay the foundation for quantum superconducting devices. Their breakthrough solves one the main challenges to quantum computing: how to transmit spin information through superconducting materials.

Every electronic device - from a supercomputer to a dishwasher - works by controlling the flow of charged electrons. But electrons can carry so much more information than just charge; electrons also spin, like a gyroscope on axis.

Harnessing electron spin is really exciting for quantum information processing because not only can an electron spin up or down - one or zero - but it can also spin any direction between the two poles. Because it follows the rules of quantum mechanics, an electron can occupy all of those positions at once. Imagine the power of a computer that could calculate all of those positions simultaneously.

A whole field of applied physics, called spintronics, focuses on how to harness and measure electron spin and build spin equivalents of electronic gates and circuits.

By using superconducting materials through which electrons can move without any loss of energy, physicists hope to build quantum devices that would require significantly less power.

But there's a problem.

According to a fundamental property of superconductivity, superconductors can't transmit spin. Any electron pairs that pass through a superconductor will have the combined spin of zero.

In work published recently inNature Physics, the Harvard researchers found a way to transmit spin information through superconducting materials.

"We now have a way to control the spin of the transmitted electrons in simple superconducting devices", stated Amir Yacoby, Professor of Physics and of Applied Physics at SEAS and senior author of the paper .

It's easy to think of superconductors as particle super highways but a better analogy would be a super carpool lane as only paired electrons can move through a superconductor without resistance.

These pairs are called Cooper Pairs and they interact in a very particular way. If the way they move in relation to each other (physicists call this momentum) is symmetric, then the pair's spin has to be asymmetric - for example, one negative and one positive for a combined spin of zero. When they travel through a conventional superconductor, Cooper Pairs' momentum has to be zero and their orbit perfectly symmetrical.

But if you can change the momentum to asymmetric - leaning toward one direction - then the spin can be symmetric. To do that, you need the help of some exotic - also known as weird - physics.

Superconducting materials can imbue non-superconducting materials with their conductive powers simply by being in close proximity. Using this principle, the researchers built a superconducting sandwich, with superconductors on the outside and mercury telluride in the middle. The atoms in mercury telluride are so heavy and the electrons move so quickly, that the rules of relativity start to apply.

"Because the atoms are so heavy, you have electrons that occupy high-speed orbits", stated Hechen Ren, co-author of the study and graduate student at SEAS. "When an electron is moving this fast, its electric field turns into a magnetic field which then couples with the spin of the electron. This magnetic field acts on the spin and gives one spin a higher energy than another."

So, when the Cooper Pairs hit this material, their spin begins to rotate.

"The Cooper Pairs jump into the mercury telluride and they see this strong spin orbit effect and start to couple differently", stated Hechen Ren. "The homogenous breed of zero momentum and zero combined spin is still there but now there is also a breed of pairs that gains momentum, breaking the symmetry of the orbit. The most important part of that is that the spin is now free to be something other than zero."

The team could measure the spin at various points as the electron waves moved through the material. By using an external magnet, the researchers could tune the total spin of the pairs.

"This discovery opens up new possibilities for storing quantum information. Using the underlying physics behind this discovery provides also new possibilities for exploring the underlying nature of superconductivity in novel quantum materials", stated Amir Yacoby.

Source: Harvard John A. Paulson School of Engineering and Applied Sciences

Back to Table of contents

Primeur weekly 2016-10-24

Focus

EUDAT Project Director Damien Lecarpentier to expand on added value of EUDAT for data storage, the success of the first DI4R Conference and on the importance of Key Performance Indicators for e-infrastructures ...

Quantum computing

Exploring defects in nanoscale devices for possible quantum computing applications ...

Quantum computers: 10-fold boost in stability achieved ...

New 3D wiring technique brings scalable quantum computers closer to reality ...

Focus on Europe

ISC 2017 seeks contributors for Conference programme ...

Middleware

Allinea brings new software performance briefings to SC16 ...

Hardware

Innovative technique for shaping light could solve bandwidth crunch ...

R&D collaboration in integrated electronic systems receives top award ...

UK Met Office installs new HPC system to significantly improve productivity of weather and climate data analysis ...

Fast data sharing with South Korea via Netherlight ...

NSF funds new projects to advance energy-efficient computing ...

Applications

Can we find more benign nanomaterials? ...

Scientists find technique to improve carbon superlattices for quantum electronic devices ...

A new class of materials could realize quantum computers ...

Rhön-Klinikum Hospitals to study how IBM Watson can support doctors in the diagnosis of rare diseases ...

Predicting jellyfish invasions at coastal power stations ...

IBM and Quest Diagnostics launch Watson-powered genomic sequencing service to help physicians bring precision cancer treatments to patients nationwide ...

A new spin on superconductivity ...

Insilico Medicine to present on recent advances in AI at BioData World in Cambridge ...

Unraveling the science behind biomass breakdown ...

T-rays will speed up computer memory by a factor of 1,000 ...

Promise of gene therapy for glaucoma shines bright in award-winning image ...

The Cloud

Amazon Web Services Cloud now available to customers from data centres in Ohio ...

IBM Cloud expands Bluemix ecosystem in China to fuel blockchain and IoT innovation ...

Atos teams with VMware to launch Digital Private Cloud offering ...

DNAstack launches genomics platform to accelerate disease research and precision medicine ...