Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Electron Rivers

17.03.2016

Usually, the movement of electrons in a real material is rather different from the flow of water in a river. However, in extraordinary materials like the metal oxide PdCoO2, “electron rivers” can exist, as predicted theoretically over fifty years ago and now demonstrated by scientists from the 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.


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

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.

Weitere Informationen:

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

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

More articles from Materials Sciences:

nachricht Simple processing technique could cut cost of organic PV and wearable electronics
06.12.2016 | Georgia Institute of Technology

nachricht InLight study: insights into chemical processes using light
05.12.2016 | Fraunhofer-Institut für Lasertechnik ILT

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Significantly more productivity in USP lasers

In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.

Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

Simple processing technique could cut cost of organic PV and wearable electronics

06.12.2016 | Materials Sciences

3-D printed kidney phantoms aid nuclear medicine dosing calibration

06.12.2016 | Medical Engineering

Robot on demand: Mobile machining of aircraft components with high precision

06.12.2016 | Power and Electrical Engineering

VideoLinks
B2B-VideoLinks
More VideoLinks >>>