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
Andrea Damascelli | EurekAlert!
One-way roads for spin currents
23.05.2018 | Singapore University of Technology and Design
Tunable diamond string may hold key to quantum memory
23.05.2018 | Harvard John A. Paulson School of Engineering and Applied Sciences
At the LASYS 2018, from June 5th to 7th, the Laser Zentrum Hannover e.V. (LZH) will be showcasing processes for the laser material processing of tomorrow in hall 4 at stand 4E75. With blown bomb shells the LZH will present first results of a research project on civil security.
At this year's LASYS, the LZH will exhibit light-based processes such as cutting, welding, ablation and structuring as well as additive manufacturing for...
There are videos on the internet that can make one marvel at technology. For example, a smartphone is casually bent around the arm or a thin-film display is rolled in all directions and with almost every diameter. From the user's point of view, this looks fantastic. From a professional point of view, however, the question arises: Is that already possible?
At Display Week 2018, scientists from the Fraunhofer Institute for Applied Polymer Research IAP will be demonstrating today’s technological possibilities and...
So-called quantum many-body scars allow quantum systems to stay out of equilibrium much longer, explaining experiment | Study published in Nature Physics
Recently, researchers from Harvard and MIT succeeded in trapping a record 53 atoms and individually controlling their quantum state, realizing what is called a...
The historic first detection of gravitational waves from colliding black holes far outside our galaxy opened a new window to understanding the universe. A...
A team led by Austrian experimental physicist Rainer Blatt has succeeded in characterizing the quantum entanglement of two spatially separated atoms by observing their light emission. This fundamental demonstration could lead to the development of highly sensitive optical gradiometers for the precise measurement of the gravitational field or the earth's magnetic field.
The age of quantum technology has long been heralded. Decades of research into the quantum world have led to the development of methods that make it possible...
02.05.2018 | Event News
13.04.2018 | Event News
12.04.2018 | Event News
23.05.2018 | Life Sciences
23.05.2018 | Life Sciences
23.05.2018 | Physics and Astronomy