Featured Research

from universities, journals, and other organizations

Pseudogap theory puts physicists closer to high temperature superconductors

Date:
March 20, 2014
Source:
University of Waterloo
Summary:
Physicists are one step closer to developing the world’s first room-temperature superconductor thanks to a new theory experts. 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.
Credit: Image courtesy of University of Waterloo

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.

Their work was published in the 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 -179C. 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.


Story Source:

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


Journal Reference:

  1. L. E. Hayward, D. G. Hawthorn, R. G. Melko, S. Sachdev. Angular Fluctuations of a Multicomponent Order Describe the Pseudogap of YBa2Cu3O6+x. Science, 2014; 343 (6177): 1336 DOI: 10.1126/science.1246310

Cite This Page:

University of Waterloo. "Pseudogap theory puts physicists closer to high temperature superconductors." ScienceDaily. ScienceDaily, 20 March 2014. <www.sciencedaily.com/releases/2014/03/140320173247.htm>.
University of Waterloo. (2014, March 20). Pseudogap theory puts physicists closer to high temperature superconductors. ScienceDaily. Retrieved July 28, 2014 from www.sciencedaily.com/releases/2014/03/140320173247.htm
University of Waterloo. "Pseudogap theory puts physicists closer to high temperature superconductors." ScienceDaily. www.sciencedaily.com/releases/2014/03/140320173247.htm (accessed July 28, 2014).

Share This




More Matter & Energy News

Monday, July 28, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

The Carbon Trap: US Exports Global Warming

The Carbon Trap: US Exports Global Warming

AP (July 28, 2014) AP Investigation: As the Obama administration weans the country off dirty fuels, energy companies are ramping-up overseas coal exports at a heavy price. (July 28) Video provided by AP
Powered by NewsLook.com
Shipping Crates Get New 'lease' On Life

Shipping Crates Get New 'lease' On Life

Reuters - Business Video Online (July 25, 2014) Shipping containers have been piling up as America imports more than it exports. Some university students in Washington D.C. are set to get a first-hand lesson in recycling. Their housing is being built using refashioned shipping containers. Lily Jamali reports. Video provided by Reuters
Powered by NewsLook.com
Europe's Highest Train Turns 80 in French Pyrenees

Europe's Highest Train Turns 80 in French Pyrenees

AFP (July 25, 2014) Europe's highest train, the little train of Artouste in the French Pyrenees, celebrates its 80th birthday. Duration: 01:05 Video provided by AFP
Powered by NewsLook.com
TSA Administrator on Politics and Flight Bans

TSA Administrator on Politics and Flight Bans

AP (July 24, 2014) TSA administrator, John Pistole's took part in the Aspen Security Forum 2014, where he answered questions on lifting of the ban on flights into Israel's Tel Aviv airport and whether politics played a role in lifting the ban. (July 24) Video provided by AP
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