Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Heusler Materials: Goldmine for Future Technologies

New quantum state of matter discovered in Heusler compounds - Researchers from Mainz and Stanford pave the way for spintronics, quantum computing and completely new physical effects

For many years, scientists at the Johannes Gutenberg University Mainz (JGU) in Germany have been world leaders in research on Heusler compounds, which are an important material class for the use in spintronic applications. Over the past few years, new application areas have emerged in the field of renewable energy, such as solar energy and thermoelectrics. And now Heusler compounds are also being considered for future technologies such as the quantum computer.

"Calculations have uncovered a new quantum state of matter in Heusler compounds, which opens up previously unimagined usage possibilities", explains Professor Claudia Felser from Mainz University. "Heusler materials are real all-rounders and a veritable goldmine for future technologies." Together with Professor Shou Cheng Zhang of Stanford University, the scientist from Mainz has shown that many Heusler compounds can behave like topological insulators (TI). TIs were discovered just five years ago.

Key discoveries in the field of physics or material sciences are often made by chance during experiments in laboratories. However, this was not the case with topological insulators. In 2006, Professor Zhang of Stanford predicted that a new quantum state of matter would be identified in nanostructures of the familiar semiconductor mercury cadmium telluride (HgTe). One year later, this was confirmed in experiments carried out by the Würzburg team led by Professor Laurens Molenkamp. Completely new mathematical concepts are required to understand the physical aspects of what has been discovered.

For almost five years now, TIs have been a hot topic in the field of solid state and material physics. Characteristic of topological insulators is the fact that the materials are actually insulators or semiconductors, although their surfaces or interfaces are made from metal - but not ordinary metal. Like superconductors, the electrons on the surfaces or interfaces do not interact with their environment - they are in a new quantum state. In contrast with superconductors, topological insulators have two non-interacting currents, one for each spin direction. These two spin currents, which are not affected by defects or impurities in the material, can be employed in the futuristic electronics field of 'spintronics' and for processing information in quantum computers.

It is now supposed that Heusler materials may have the same capabilities. Heusler compounds are made up of three elements, which often have semiconductor or magnetic properties. This compound class was discovered by Fritz Heusler back around 1900. One special feature of these compounds is that they exhibit characteristics other than those that might be expected in view of the elements of which they are composed. The first Heusler compound, for example, was made from the non-magnetic elements copper, manganese, and aluminium. Yet, Cu2MnAl acts as a ferromagnet, even at room temperature. On the other hand, a semiconductor can result when three metals are combined. New semiconductors can be designed in the class of Heusler materials with regard to the field of renewable energies; they can be used in solar cells or in thermoelectric applications, for converting heat into electricity. Mainz is internationally renowned as a major location for the design and synthesis of Heusler materials. Important discoveries with regard to Heusler compounds, their properties, and their uses in a wide range of potential applications have been made in Mainz.

The news that Heusler materials are now being considered as possible topological insulators has met with excitement all over the world. "There are two reasons for this," explains Professor Felser. "On the one hand, this large material class with over 1,000 known representatives contains more than 50 compounds that bear the hallmark of TIs. And on the other hand, it is now possible to design completely new physical effects. As the materials are made up of three elements, they can offer a range of other interesting features in addition to the topological quantum state." It is now possible to combine two quantum states such as superconductivity and topological surface effects. This paves the way for completely new and as yet undiscovered characteristics, some of which have already been predicted. "It was previously not considered possible to combine all these possibilities in just one material," explains Professor Felser.

The leading scientific journal Nature Materials published three articles on this topic in light of these disclosures - the article from the research team in Stanford and Mainz, a contribution submitted by Princeton a short time later, and a discussion of the sensational discovery.

Petra Giegerich | idw
Further information:

More articles from Physics and Astronomy:

nachricht Gamma ray camera offers new view on ultra-high energy electrons in plasma
28.10.2016 | American Physical Society

nachricht Scientists measure how ions bombard fusion device walls
28.10.2016 | American Physical Society

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: Novel light sources made of 2D materials

Physicists from the University of Würzburg have designed a light source that emits photon pairs. Two-photon sources are particularly well suited for tap-proof data encryption. The experiment's key ingredients: a semiconductor crystal and some sticky tape.

So-called monolayers are at the heart of the research activities. These "super materials" (as the prestigious science magazine "Nature" puts it) have been...

Im Focus: Etching Microstructures with Lasers

Ultrafast lasers have introduced new possibilities in engraving ultrafine structures, and scientists are now also investigating how to use them to etch microstructures into thin glass. There are possible applications in analytics (lab on a chip) and especially in electronics and the consumer sector, where great interest has been shown.

This new method was born of a surprising phenomenon: irradiating glass in a particular way with an ultrafast laser has the effect of making the glass up to a...

Im Focus: Light-driven atomic rotations excite magnetic waves

Terahertz excitation of selected crystal vibrations leads to an effective magnetic field that drives coherent spin motion

Controlling functional properties by light is one of the grand goals in modern condensed matter physics and materials science. A new study now demonstrates how...

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

All Focus news of the innovation-report >>>



Event News

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

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Prototype device for measuring graphene-based electromagnetic radiation created

28.10.2016 | Power and Electrical Engineering

Gamma ray camera offers new view on ultra-high energy electrons in plasma

28.10.2016 | Physics and Astronomy

When fat cells change their colour

28.10.2016 | Life Sciences

More VideoLinks >>>