The goal is topological insulators (TI), man-made crystals that are able to conduct electrical current on their surfaces, while acting as insulators throughout the interior of the crystal. Discovering TIs has become of great interest to scientists, but because of the lack of a rational blueprint for creating them, researchers have had to rely on trial-and-error approaches, with limited success to date.
Because of their unique properties, TIs can be created that conduct electricity more efficiently while also being much smaller that conventional wires or devices. They are ideal candidates to become quantum electronics devices, the Duke researchers said.
The "key" developed by the Duke investigators is a mathematical formulation that unlocks the data stored in a database of potential TI ingredients. It provides specific recipes for searching for TIs with the desired properties.
In November, Stefano Curtarolo, professor of mechanical engineering and materials sciences and physics at Duke's Pratt School of Engineering and founder of the Duke's Center for Materials Genomics, and colleagues reported the establishment of a materials genome repository (aflowlib.org) which allows scientists to stop using trial-and-error methods in the search for efficient alloys.
The project developed by the Duke engineers covers thousands of compounds, and provides detailed recipes for creating the most efficient combinations for a particular purpose, much like hardware stores mix different colors of paint to achieve the desired result. The project is the keystone of the newly formed Duke's Center for Materials Genomics.
"While extremely helpful and important, a database is intrinsically a sterile repository of information, without a soul and without life. We need to find the materials' 'genes,'" said Curtarolo. "We have developed what we call the 'topological descriptor,' that when applied to the database can provide the directions for producing crystals with desired properties."
While developing the key to this database, the team also discovered a new class of systems that could not have been anticipated without such a "genetic" approach.
The Duke research was reported online in the journal Nature Materials. The work was supported by the Office of Navy Research and the National Science Foundation.
The new descriptor developed by the Duke team basically can determine status of any specific combination of element under investigation. On one end of the spectrum, Curtarolo explained, is "fragile."
"We can rule those combinations out because, what good is a new type of crystal if it would be too difficult to grow, or if grown, would not likely survive?" Curtarolo said. A second group of combinations would be a middle group termed "feasible."
But what excites Curtarolo most are those combinations found to be "robust." These crystals are stable and can be easily and efficiently produced. Just as importantly, these crystals can be grown in different directions,which gives them the advantage of tailored electrical properties by simple growth processes.
While TIs are currently in the experimental stage, Curtarolo believes that with this new tool, scientists should have a powerful framework for engineering a wide variety of them.
Kesong Yang, a post-doctoral fellow in Curtarolo's laboratory, is first author of the paper. Other members of the team were Duke's Shidong Wang, Wahyu Setyawan, Pacific Northwest Laboratory and Marco Buongiorno Nardelli, University of North Texas and the Oak Ridge National Laboratory.
Citation: "A Search Model for Topological Insulators with High-Throughput Robustness Descriptors," Kesong Yang, et. al., Nature Materials [DOI: 10.1038/NMAT3332].
Richard Merritt | EurekAlert!
A materials scientist’s dream come true
21.08.2018 | Friedrich-Alexander-Universität Erlangen-Nürnberg
Novel sensors could enable smarter textiles
17.08.2018 | University of Delaware
There are currently great hopes for solid-state batteries. They contain no liquid parts that could leak or catch fire. For this reason, they do not require cooling and are considered to be much safer, more reliable, and longer lasting than traditional lithium-ion batteries. Jülich scientists have now introduced a new concept that allows currents up to ten times greater during charging and discharging than previously described in the literature. The improvement was achieved by a “clever” choice of materials with a focus on consistently good compatibility. All components were made from phosphate compounds, which are well matched both chemically and mechanically.
The low current is considered one of the biggest hurdles in the development of solid-state batteries. It is the reason why the batteries take a relatively long...
New design tool automatically creates nanostructure 3D-print templates for user-given colors
Scientists present work at prestigious SIGGRAPH conference
Most of the objects we see are colored by pigments, but using pigments has disadvantages: such colors can fade, industrial pigments are often toxic, and...
Scientists at the University of California, Los Angeles present new research on a curious cosmic phenomenon known as "whistlers" -- very low frequency packets...
Scientists develop first tool to use machine learning methods to compute flow around interactively designable 3D objects. Tool will be presented at this year’s prestigious SIGGRAPH conference.
When engineers or designers want to test the aerodynamic properties of the newly designed shape of a car, airplane, or other object, they would normally model...
Researchers from TU Graz and their industry partners have unveiled a world first: the prototype of a robot-controlled, high-speed combined charging system (CCS) for electric vehicles that enables series charging of cars in various parking positions.
Global demand for electric vehicles is forecast to rise sharply: by 2025, the number of new vehicle registrations is expected to reach 25 million per year....
17.08.2018 | Event News
08.08.2018 | Event News
27.07.2018 | Event News
21.08.2018 | Materials Sciences
20.08.2018 | Information Technology
20.08.2018 | Life Sciences