Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Ultrafast laser pulses shed light on elusive superconducting mechanism: U of British Columbia

30.03.2012
International team that includes University of British Columbia physicists has used ultra-fast laser pulses to identify the microscopic interactions that drive high-temperature superconductivity

An international team that includes University of British Columbia physicists has used ultra-fast laser pulses to identify the microscopic interactions that drive high-temperature superconductivity.

In the experiment, to be outlined this Friday in the journal Science, electrons in a prototypical copper-oxide superconductor were excited by extremely short 100-femtosecond (0.0000000000001-second) laser pulses.

As the material's electrons relax back to an equilibrium state, they release their excess energy via deformation of the superconductor's atomic lattice (phonons) or perturbation of its magnetic correlations (spin fluctuations).

The researchers were able to capture very fine grained data on the speed of the relaxation process and its influence on the properties of the superconducting system, showing that the high-critical temperature of these compounds can be accounted for by purely electronic (magnetic) processes.

"This new technique offers us our best window yet on the interactions that govern the formation of these elusive superconducting properties--both across time and across a wide range of characteristic energies," says UBC Associate Professor Andrea Damascelli, Canada Research Chair in Electronic Structure of Solids with the Department of Physics and Astronomy and the UBC Quantum Matter Institute.

"We're now able to begin to disentangle the different interactions that contribute to this fascinating behavior."

Superconductivity--the phenomenon of conducting electricity with no resistance--occurs in some materials at very low temperatures. High-temperature cuprate superconductors are capable of conducting electricity without resistance at temperatures as high as -140 degrees Celsius.

The key mechanism that allows the carriers to flow without resistance in superconductors stems from an effective pairing between electrons. In conventional metallic superconductors, this pairing mechanism is well understood as phonon-mediated. In copper-oxides, the nature of the low-resistance interaction between the electrons has remained a mystery.

"This breakthrough in the understanding of the puzzling properties of copper-oxides paves the way to finally solving the mystery of high-temperature superconductivity and revealing the key knobs for engineering new superconducting materials with even higher transition temperatures," says the paper's lead author Claudio Giannetti, a researcher with Italy's Università Cattolica del Sacro Cuore and visiting professor at UBC's Quantum Matter Institute.

The international collaboration also involved contributions from Japanese, Swiss and American researchers.

The UBC portion of the research program was funded by the Killam Trusts, the Canada Research Chair program, the Sloan Foundation, the Natural Sciences and Engineering Research Council of Canada, the Canada Foundation for Innovation, and the Canadian Institute for Advanced Research Quantum Materials program.

Andrea Damascelli
Department of Physics & Astronomy
University of British Columbia
P: (604) 822-4551
E: damascelli@physics.ubc.ca
Chris Balma
UBC Faculty of Science
P: (604) 822-5082
E: balma@science.ubc.ca

Andrea Damascelli | EurekAlert!
Further information:
http://www.ubc.ca

More articles from Physics and Astronomy:

nachricht Interstellar seeds could create oases of life
28.08.2015 | Harvard-Smithsonian Center for Astrophysics

nachricht Draw out of the predicted interatomic force
28.08.2015 | Hiroshima 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: OU astrophysicist and collaborators find supermassive black holes in quasar nearest Earth

A University of Oklahoma astrophysicist and his Chinese collaborator have found two supermassive black holes in Markarian 231, the nearest quasar to Earth, using observations from NASA's Hubble Space Telescope.

The discovery of two supermassive black holes--one larger one and a second, smaller one--are evidence of a binary black hole and suggests that supermassive...

Im Focus: What would a tsunami in the Mediterranean look like?

A team of European researchers have developed a model to simulate the impact of tsunamis generated by earthquakes and applied it to the Eastern Mediterranean. The results show how tsunami waves could hit and inundate coastal areas in southern Italy and Greece. The study is published today (27 August) in Ocean Science, an open access journal of the European Geosciences Union (EGU).

Though not as frequent as in the Pacific and Indian oceans, tsunamis also occur in the Mediterranean, mainly due to earthquakes generated when the African...

Im Focus: Self-healing landscape: landslides after earthquake

In mountainous regions earthquakes often cause strong landslides, which can be exacerbated by heavy rain. However, after an initial increase, the frequency of these mass wasting events, often enormous and dangerous, declines, in fact independently of meteorological events and aftershocks.

These new findings are presented by a German-Franco-Japanese team of geoscientists in the current issue of the journal Geology, under the lead of the GFZ...

Im Focus: FIC Proteins Send Bacteria Into Hibernation

Bacteria do not cease to amaze us with their survival strategies. A research team from the University of Basel's Biozentrum has now discovered how bacteria enter a sleep mode using a so-called FIC toxin. In the current issue of “Cell Reports”, the scientists describe the mechanism of action and also explain why their discovery provides new insights into the evolution of pathogens.

For many poisons there are antidotes which neutralize their toxic effect. Toxin-antitoxin systems in bacteria work in a similar manner: As long as a cell...

Im Focus: Fraunhofer IPA develops prototype of intelligent care cart

It comes when called, bringing care utensils with it and recording how they are used: Fraunhofer IPA is developing an intelligent care cart that provides care staff with physical and informational support in their day-to-day work. The scientists at Fraunhofer IPA have now completed a first prototype. In doing so, they are continuing in their efforts to improve working conditions in the care sector and are developing solutions designed to address the challenges of demographic change.

Technical assistance systems can improve the difficult working conditions in residential nursing homes and hospitals by helping the staff in their work and...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Networking conference in Heidelberg for outstanding mathematicians and computer scientists

20.08.2015 | Event News

Scientists meet in Münster for the world’s largest Chitin und Chitosan Conference

20.08.2015 | Event News

Large agribusiness management strategies

19.08.2015 | Event News

 
Latest News

Interstellar seeds could create oases of life

28.08.2015 | Physics and Astronomy

An ounce of prevention: Research advances on 'scourge' of transplant wards

28.08.2015 | Health and Medicine

Fish Oil-Diet Benefits May be Mediated by Gut Microbes

28.08.2015 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>