Electron Rivers

One of the created “electron rivers”. The flow takes place along the purple channel, and is studied using instruments attached to the blue, red, green and gold-coloured parts. MPI CPfS

Although one might think that when there is an electric current in a metal, the electrons flow like water would in a pipe, that is actually not the case. Their motion is impeded because they bounce off the atoms that make up the metallic crystal, and the flow process is not nearly as interesting as the ones that we can see at play any time we sit next to a river.

For ‘electron rivers’ to exist, one needs to find extraordinary materials in which the collisions with the host atoms are thousands of times weaker than usual. Although this possibility, known as ‘electronic hydrodynamics’, was predicted theoretically over fifty years ago, it has taken until now to reach the new regime in a bulk material.

In Science Magazine (volume 351, 4th March 2016; see also the article “Perspectives” by J. Zaanen), three papers simultaneously reported experimental success. The groups of Philip Kim at Harvard and Andre Geim at Manchester worked on graphene, but the contribution from the Mackenzie and Moll groups from the Max Planck Institute for Chemical Physics of Solids Dresden was based on an oxide metal.

Our material of choice, PdCoO2, has an astonishingly high electrical conductivity, making it possible to look for hydrodynamic effects. To reveal their presence, we sculpted successively narrower channels, and studied how easily the electrons could flow through them.

By combining our results with a special theory that is able to model hydrodynamic effects, we were able to show that we had indeed created the long-predicted electron rivers. The research opens new frontiers in research into electron behavior in ultra-pure materials.

The richness seen in the flow of water might be observable in the flow of electrons, and some of this richness might one day also lead to the invention of new electronic devices. We hope to play a leading role in these developments.

The research at the Max Planck Institute for Chemical Physics of Solids (MPI CPfS) in Dresden aims to discover and understand new materials with unusual properties. In close cooperation, chemists and physicists (including chemists working on synthesis, experimentalists and theoreticians) use the most modern tools and methods to examine how the chemical composition and arrangement of atoms, as well as external forces, affect the magnetic, electronic and chemical properties of the compounds. New quantum materials, physical phenomena and materials for energy conversion are the result of this interdisciplinary collaboration.

The MPI CPfS (www.cpfs.mpg.de) is part of the Max Planck Society and was founded in 1995 in Dresden. It consists of around 280 employees, of which about 180 are scientists, including 70 doctoral students.

http://www.cpfs.mpg.de/2664542/20160310

Media Contact

Ingrid Rothe Max-Planck-Institut für Chemische Physik fester Stoffe

All latest news from the category: Materials Sciences

Materials management deals with the research, development, manufacturing and processing of raw and industrial materials. Key aspects here are biological and medical issues, which play an increasingly important role in this field.

innovations-report offers in-depth articles related to the development and application of materials and the structure and properties of new materials.

Back to home

Comments (0)

Write a comment

Newest articles

Dan Shugar, an associate professor with the Department of Earth, Energy and Environment in the Faculty of Science at the University of Calgary, says it’s important to analyse what happened in the Sikkim flood and what can be learned from it as rapid climate warning affects mountain regions around the world. Image Credit: Courtesy: Dan Shugar/University of Calgary

Studying Sikkim Floods: Insights for Disaster Preparedness

UCalgary scientist says it’s important to determine what happened and what can be learned  Experts from the global Earth science community – including a scientist from the University of Calgary…

Mona Eskandari, UCR assistant professor of mechanical engineering. Image Credit: Jonathan Alcorn/ UCR

New Study Sheds Light on Pelvic Tissue Tears in Childbirth

Grant enables study into mechanical properties of episiotomy cuts  Millions of women undergo episiotomies during childbirth every year, yet the mechanics behind these surgical cuts remain largely unstudied. A new…

Dr. Mitzman with da Vinci 5 robotic surgical system. Image Credit: Emily Bade

New Robotic Surgical Systems Transforming Patient Care

Discover how Huntsman Cancer Institute is transforming surgical care with the new da Vinci 5 robotic systems. Learn about their precision, patient benefits, and commitment to advancing minimally invasive procedures…