Superconductivity breakthroughs

March 19, 2015

The Canadian research community on high-temperature superconductivity continues to lead this exciting scientific field with groundbreaking results coming hot on the heels of big theoretical questions.

The latest breakthrough, which will be published March 20 in Science, answers a key question on the microscopic electronic structure of cuprate superconductors, the most celebrated material family in our quest for true room-temperature superconductivity.

This result is the product of a longstanding close collaboration between the University of British Columbia Quantum Matter Institute and the Canadian Light Source. In fact, this is the third Science paper to come out of this remarkably fruitful collaboration this past year, and the first to feature an all-Canadian effort.

The collaborators work at the forefront of research into high-temperature superconductors, an exciting class of materials exhibiting superconductivity at temperatures as comparatively warm as -100?C. As frigid as such temperature may sound, it outperforms by far traditional superconductors, which operate at closer to -270?C, or a few degrees from absolute zero - the point where all motion stops."

In the superconducting state, electricity flows with absolutely no resistance, which means no energy is lost and no heat is generated. Combined, these properties allow for large 'supercurrents' that could not be realized in ordinary wires.

For this reason, superconductors are already used to provide the large magnetic fields needed for Magnetic Resonance Imaging, but the cooling systems needed to make them work are costly and impede other potential uses. Some of the major, transformative applications of room-temperature superconductivity include magnetic levitation trains and lossless power lines. (Imagine getting rid of that pesky delivery charge on your energy bill--room temperature superconductivity could make it possible.)

The paper's lead author, Riccardo Comin, a UBC graduate from Andrea Damascelli's group and now a post-doctoral fellow at the University of Toronto, compares the movement of electrons in a superconductor to birds flying in formation, coherently and without collisions. In physics-speak, the electrons move coherently and in phase, and no energy is lost as they drift smoothly along.

In cuprate superconductors, another state blocks and interacts with superconductivity: the charge-density-wave, in which the electrons assume a static pattern, different from the pattern that the material's crystal structure defines.

You can also think of the superconducting electrons like cars on a highway, all moving the same speed and direction, the picture of efficiency. But the charge-density-wave state acts like a patterned traffic jam: no movement, anywhere.

Understanding what causes this pattern is thought to be a key step to understanding superconductivity, but even pinning down the nature of the pattern has been elusive. Major theoretical models predict either a parallel line structure, or a checkerboard pattern. Unfortunately, even with advanced synchrotron techniques, it has proved impossible to see the difference between the two models.

That is, until Comin's latest results in Science, which show that the cuprate superconductor in question has a stripe-like pattern rather than a checkerboard one. The UBC-CLS team used an unconventional experimental approach to reconstruct a 2-dimensional model of the static electron pattern from 1-dimensional scans--much like the tomographic reconstructions used for medical purposes.

These results offer new fundamental insights helping hone the search for room temperature superconductivity. However, more challenging questions remain. Among these puzzles: What is the driving force behind the tendency of electrons to move together coherently in the superconducting state, and how can the superconductivity transition temperature be further enhanced? Despite almost 30 years of history, the field of high temperature superconductivity is more alive than ever.

Canadian Light Source, Inc.

Related Superconductors Articles from Brightsurf:

Progress in electronic structure and topology in nickelates superconductors
Recently, superconductivity was discovered in the hole-doped nickelates, wh ich provide us a new platform to study the mechanism of high-temperature superconductivity.

UCF researcher zeroes in on critical point for improving superconductors
Developing a practical ''room temperature'' superconductor is a feat science has yet to achieve.

Connecting two classes of unconventional superconductors
The understanding of unconventional superconductivity is one of the most challenging and fascinating tasks of solid-state physics.

Superconductors are super resilient to magnetic fields
A Professor at the University of Tsukuba provides a new theoretical mechanism that explains the ability of superconductive materials to bounce back from being exposed to a magnetic field.

New advance in superconductors with 'twist' in rhombohedral graphite
An international research team led by The University of Manchester has revealed a nanomaterial that mirrors the 'magic angle' effect originally found in a complex man-made structure known as twisted bilayer graphene -- a key area of study in physics in recent years.

A new way towards super-fast motion of vortices in superconductors discovered
An international team of scientists from Austria, Germany and Ukraine has found a new superconducting system in which magnetic flux quanta can move at velocities of 10-15 km/s.

Controlling superconductors with light
IBS scientists has reported a conceptually new method to study the properties of superconductors using optical tools.

Superconductors with 'zeitgeist' -- When materials differentiate between past and future
Physicists at TU Dresden have discovered spontaneous static magnetic fields with broken time-reversal symmetry in a class of iron-based superconductors.

Hydrogen blamed for interfering with nickelate superconductors synthesis
Prof. ZHONG Zhicheng's team at the Ningbo Institute of Materials Technology and Engineering has investigated the electronic structure of the recently discovered nickelate superconductors NdNiO2. They successfully explained the experimental difficulties in synthesizing superconducting nickelates, in cooperation with Prof.

A closer look at superconductors
From sustainable energy to quantum computers: high-temperature superconductors have the potential to revolutionize today's technologies.

Read More: Superconductors News and Superconductors Current Events is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to