Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Pseudogap theory puts physicists closer to high temperature superconductors

21.03.2014

Physicists are one step closer to developing the world’s first room-temperature superconductor thanks to a new theory from the University of Waterloo, Harvard and Perimeter Institute.

The theory explains the transition phase to superconductivity, or “pseudogap” phase, which is one of the last obstacles to developing the next generation of superconductors and one of the major unsolved problems of theoretical condensed matter physics.


Right to left: Prof. David Hawthorn, Prof. Roger Melko, and Lauren Hayward. They are pictured in front of Waterloo’s SHARCNET supercomputer which they used to perform the calculations.

Their work was published in this week’s issue of the prestigious journal Science.

Superconductivity is the phenomenon where electricity flows with no resistance and no energy loss. Most materials need to be cooled to ultra-low temperatures with liquid helium in order to achieve a superconductive state.

The team includes Professor Roger Melko, Professor David Hawthorn and doctoral student Lauren Hayward from Waterloo’s Physics and Astronomy Department, and Harvard Physics Professor Subir Sachev. Roger Melko also holds a Canada Research Chair in Computational Quantum Many-Body Physics.

“This amazing scientific collaboration actually came about by chance over lunch at the Perimeter Institute between Subir and myself,” said Hawthorn.

Hawthorn showed Sachdev his latest experimental data on a superconducting material made of Copper and the elements Yttrium and Barium. The material, YBa2Cu3O6+x, had an unexplained temperature dependence. Sachdev had a theory but needed expert help with the complex set of calculations to prove it. That’s where Melko and Hayward stepped in and developed the computer code to solve Sachdev’s equations.

Melko and Sachdev already knew each other through Perimeter Institute, where Melko is an associate faculty member and Sachdev is a Distinguished Research Visiting Chair.

“The results all came together in a matter of weeks,” said Melko. “It really speaks to the synergy we have between Waterloo and Perimeter Institute.”

To understand why room-temperature superconductivity has remained so elusive, physicists have turned their sights to the phase that occurs just before superconductivity takes over: the mysterious “pseudogap” phase.

“Understanding the pseudogap is as important as understanding superconductivity itself,” said Melko.

The cuprate, YBa2Cu3O6+x, is one of the few materials known to be superconductive at higher temperatures, but scientists are so far unable to achieve superconductivity in this material above -179°C. This new study found that YBa2Cu3O6+x oscillates between two quantum states during the pseudogap, one of which involves charge-density wave fluctuations. These periodic fluctuations in the distribution of the electrical charges are what destabilize the superconducting state above the critical temperature.

Once the material is cooled below the critical temperature, the strength of these fluctuations falls and the superconductivity state takes over.

Superconducting magnets are currently used in MRI machines and complex particle accelerators, but the cost of cooling materials using Helium makes them very expensive. Materials that achieve superconductivity at a higher temperature could unlock the technology for new smart power grids and advanced power storage units.

The group plans to extend their work both theoretically and experimentally to understand more about the fundamental nature of cuprates.

About the University of Waterloo

In just half a century, the University of Waterloo, located at the heart of Canada's technology hub, has become one of Canada's leading comprehensive universities with 35,000 full- and part-time students in undergraduate and graduate programs. Waterloo, as home to the world's largest post-secondary co-operative education program, embraces its connections to the world and encourages enterprising partnerships in learning, research and discovery. In the next decade, the university is committed to building a better future for Canada and the world by championing innovation and collaboration to create solutions relevant to the needs of today and tomorrow. For more information about Waterloo, please visit www.uwaterloo.ca.

-30-

Media Contact

Nick Manning
University of Waterloo
519-888-4451
226-929-7627
www.uwaterloo.ca/news
@uWaterlooNews

Attention broadcasters: Waterloo has facilities to provide broadcast quality audio and video feeds with a double-ender studio. Please contact us to book.

Nick Manning | EurekAlert!

More articles from Physics and Astronomy:

nachricht Streamlining accelerated computing for industry
24.08.2016 | DOE/Oak Ridge National Laboratory

nachricht Lehigh engineer discovers a high-speed nano-avalanche
24.08.2016 | Lehigh University

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

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

Im Focus: Streamlining accelerated computing for industry

PyFR code combines high accuracy with flexibility to resolve unsteady turbulence problems

Scientists and engineers striving to create the next machine-age marvel--whether it be a more aerodynamic rocket, a faster race car, or a higher-efficiency jet...

Im Focus: X-ray optics on a chip

Waveguides are widely used for filtering, confining, guiding, coupling or splitting beams of visible light. However, creating waveguides that could do the same for X-rays has posed tremendous challenges in fabrication, so they are still only in an early stage of development.

In the latest issue of Acta Crystallographica Section A: Foundations and Advances , Sarah Hoffmann-Urlaub and Tim Salditt report the fabrication and testing of...

Im Focus: Piggyback battery for microchips: TU Graz researchers develop new battery concept

Electrochemists at TU Graz have managed to use monocrystalline semiconductor silicon as an active storage electrode in lithium batteries. This enables an integrated power supply to be made for microchips with a rechargeable battery.

Small electrical gadgets, such as mobile phones, tablets or notebooks, are indispensable accompaniments of everyday life. Integrated circuits in the interiors...

Im Focus: UCI physicists confirm possible discovery of fifth force of nature

Light particle could be key to understanding dark matter in universe

Recent findings indicating the possible discovery of a previously unknown subatomic particle may be evidence of a fifth fundamental force of nature, according...

Im Focus: Wi-fi from lasers

White light from lasers demonstrates data speeds of up to 2 GB/s

A nanocrystalline material that rapidly makes white light out of blue light has been developed by KAUST researchers.

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

The energy transition is not possible without Geotechnics

25.08.2016 | Event News

New Ideas for the Shipping Industry

24.08.2016 | Event News

A week of excellence: 22 of the world’s best computer scientists and mathematicians in Heidelberg

12.08.2016 | Event News

 
Latest News

Environmental DNA uncovers biodiversity in rivers

30.08.2016 | Ecology, The Environment and Conservation

Solar houses scientifically evaluated

30.08.2016 | Power and Electrical Engineering

Amazon forests: Biodiversity can help mitigate climate risks

30.08.2016 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>