Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


New material has highest electron mobility among known layered magnetic materials


Properties make it promising candidate for new areas like magnetic twistronic devices and spintronics, as well as advances in data storage and device design

All the elements are there to begin with, so to speak; it's just a matter of figuring out what they are capable of - alone or together. For Leslie Schoop's lab, one recent such investigation has uncovered a layered compound with a trio of properties not previously known to exist in one material.

A material made at Princeton has highest electron mobility among known layered magnetic materials. Electrons inside the material, gadolinium tritelluride, are able to travel at high speeds with minimal scattering, reducing the heat dissipation of any electronic devices built from it.

Image by Shiming Lei

With an international interdisciplinary team, Schoop, assistant professor of chemistry, and Postdoctoral Research Associate Shiming Lei, published a paper last week in Science Advances reporting that the van der Waals material gadolinium tritelluride (GdTe3) displays the highest electronic mobility among all known layered magnetic materials. In addition, it has magnetic order, and can easily be exfoliated.

Combined, these properties make it a promising candidate for new areas like magnetic twistronic devices and spintronics, as well as advances in data storage and device design.

The Schoop team initially uncovered these unique characteristics in early 2018 shortly after beginning the project. Their first success was in demonstrating that GdTe3 is easily exfoliable down to ultrathin flakes below 10nm. Subsequently, the team spent two years refining the purity of the material crystals to a state that only served to amplify the results. The lab has already shipped a number of samples to researchers eager to explore how the compound fits into a category previously occupied only by black phosphorous and graphite. High mobility is rare in layered materials.

The properties detailed in the study, described as quantum oscillations or "wiggles" that can be measured, are so pronounced that they were observed without the special probes and equipment generally found in national laboratories.

"Usually, if you see these oscillations, it depends partly on the quality of your sample. We really sat down and made the best crystals possible. Over the course of two years we improved the quality, so that these oscillations became more and more dramatic," said Schoop. "But the first samples already showed them, even though with the first crystals we grew we didn't know exactly what we were doing," Schoop said.

"It was very exciting for us. We saw these results of highly mobile electrons in this material that we didn't expect. Of course we were hoping for good results. But I didn't anticipate it to be as dramatic," Schoop added.

Lei characterized the news as a "breakthrough" largely because of the high mobility. "Adding this material into the zoo of 2D van der Waals materials is like adding a newly discovered ingredient for cooking, which allows for new flavors and dishes," he said.

"So first, you get these materials out. The next thing is identifying the potential: what is the function of the device you can make from it? What is the performance we can further improve as a next generation of materials along this line?"

A rare-earth tritelluride, GdTe3 has a carrier mobility beyond 60,000 cm2V-1s-1. This means that if a field of one volt per cm is applied to the material, the electrons move with a net speed of 60,000 cm per second. To compare, mobilities in other magnetic materials are often found to be only a few hundred cm2V-1s-1 .

"High mobility is important because this means that electrons inside the materials are able to travel at high speeds with minimal scattering, thus reducing the heat dissipation of any electronic devices built from it," said Lei.

Van der Waals materials - in which the layers are bound by a weak force - are the parent compounds of 2D materials. Researchers are studying them for next-generation device fabrication and also for use in twistronics, first described in the science community only a few years ago. With twistronics, the layers of 2D materials are misaligned or twisted as they lay atop one another. The judicious misalignment of the crystal lattice can change electrical, optical and mechanical properties in ways that may yield new opportunities for applications.

In addition, it was discovered some 15 years ago that van der Waals materials could be exfoliated down to the thinnest layer by using something as commonplace as scotch tape. This revelation excited many new developments in physics. Finally, 2D materials were only recently revealed to exhibit magnetic order, in which the spins of electrons are aligned to each other. All "thin" devices -- hard drives, for example - are based on materials ordering magnetically in different ways that produce different efficiencies.

"We have found this material where the electrons shoot through as on a highway - perfect, very easily, fast," said Schoop. "Having this magnetic order in addition and the potential to go to two dimensions is just something that was uniquely new for this material."

The results of the study are a strong showing for Schoop's young lab, established just over two years ago. They are the product of a collaboration with the Princeton Center for Complex Materials, an NSF-funded Materials Research Science and Engineering Center, and co-authors Nai Phuan Ong, Sanfeng Wu, and Ali Yazdani, all faculty with Princeton's Department of Physics.

To fully understand the electronic and magnetic properties of GdTe3, the team also collaborated with Boston College for exfoliation tests, and Argonne National Laboratory and the Max Planck Institute for Solid State Research to understand the electronic structure of the material using synchroton radiation.

From a broader perspective, what satisfied Schoop most about the study was the "chemical intuition" that led the team to begin the investigation with GdTe3 in the first place. They suspected there would be promising results. But the fact that GdTe3 yielded them so quickly and emphatically is a sign, said Schoop, that chemistry has significant contributions to make to the field of solid state physics.

"We're a group in the chemistry department and we figured out that this material should be of interest for highly mobile electrons based on chemical principles," said Schoop. "We were thinking about how the atoms were arranged in these crystals and how they should be bonded to each other, and not based on physical means, which is often understanding the energy of electrons based on Hamiltonians.

"But we took a very different approach, much more related to drawing pictures, like chemists do, related to orbitals and things like that," she said. "And we were successful with this approach. It's just such a unique and different approach in thinking about exciting materials."


The paper, "High mobility in a van der Waals layered antiferromagnetic metal," by S. Lei, J. Lin, Y. Jia, M. Gray, A. Topp, G. Farahi, S. Klemenz, T. Gao, F. Rodolakis, J. L. McChesney, C.R. Ast, A. Yazdani, K. S. Burch, S. Wu, N.P. Ong, and L.M. Schoop appeared in an online issue of Science Advances on Feb. 7, 2020, (Lei et. al., Sci. Adv. 6, eaay6407 2020).

This research was supported by the National Science Foundation through the Princeton Center for Complex Materials (Award # NSF DMR 1420541). L.M.S. was supported by a Beckman Young Investigator award from the Arnold and Mabel Beckman foundation. L.M.S. and S.L. were additionally supported by a MURI grant on Topological Insulators from the Army Research Office (grant number ARO W911NF-12-1-0461).

Media Contact

Catherine Zandonella


Catherine Zandonella | EurekAlert!
Further information:

More articles from Materials Sciences:

nachricht Graphene-based actuator swarm enables programmable deformation
02.04.2020 | Science China Press

nachricht How to remove dirt easily
02.04.2020 | Max-Planck-Institut für Polymerforschung

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: A sensational discovery: Traces of rainforests in West Antarctica

90 million-year-old forest soil provides unexpected evidence for exceptionally warm climate near the South Pole in the Cretaceous

An international team of researchers led by geoscientists from the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research (AWI) have now...

Im Focus: Blocking the Iron Transport Could Stop Tuberculosis

The bacteria that cause tuberculosis need iron to survive. Researchers at the University of Zurich have now solved the first detailed structure of the transport protein responsible for the iron supply. When the iron transport into the bacteria is inhibited, the pathogen can no longer grow. This opens novel ways to develop targeted tuberculosis drugs.

One of the most devastating pathogens that lives inside human cells is Mycobacterium tuberculosis, the bacillus that causes tuberculosis. According to the...

Im Focus: Physicist from Hannover Develops New Photon Source for Tap-proof Communication

An international team with the participation of Prof. Dr. Michael Kues from the Cluster of Excellence PhoenixD at Leibniz University Hannover has developed a new method for generating quantum-entangled photons in a spectral range of light that was previously inaccessible. The discovery can make the encryption of satellite-based communications much more secure in the future.

A 15-member research team from the UK, Germany and Japan has developed a new method for generating and detecting quantum-entangled photons at a wavelength of...

Im Focus: Junior scientists at the University of Rostock invent a funnel for light

Together with their colleagues from the University of Würzburg, physicists from the group of Professor Alexander Szameit at the University of Rostock have devised a “funnel” for photons. Their discovery was recently published in the renowned journal Science and holds great promise for novel ultra-sensitive detectors as well as innovative applications in telecommunications and information processing.

The quantum-optical properties of light and its interaction with matter has fascinated the Rostock professor Alexander Szameit since College.

Im Focus: Stem Cells and Nerves Interact in Tissue Regeneration and Cancer Progression

Researchers at the University of Zurich show that different stem cell populations are innervated in distinct ways. Innervation may therefore be crucial for proper tissue regeneration. They also demonstrate that cancer stem cells likewise establish contacts with nerves. Targeting tumour innervation could thus lead to new cancer therapies.

Stem cells can generate a variety of specific tissues and are increasingly used for clinical applications such as the replacement of bone or cartilage....

All Focus news of the innovation-report >>>



Industry & Economy
Event News

13th AKL – International Laser Technology Congress: May 4–6, 2022 in Aachen – Laser Technology Live already this year!

02.04.2020 | Event News

“4th Hybrid Materials and Structures 2020” takes place over the internet

26.03.2020 | Event News

Most significant international Learning Analytics conference will take place – fully online

23.03.2020 | Event News

Latest News

Scientists see energy gap modulations in a cuprate superconductor

02.04.2020 | Physics and Astronomy

AI finds 2D materials in the blink of an eye

02.04.2020 | Information Technology

New 3D cultured cells mimic the progress of NASH

02.04.2020 | Health and Medicine

Science & Research
Overview of more VideoLinks >>>