September 25, 2021


Connecting People

Quantum materials cut closer than ever — ScienceDaily

DTU and Graphene Flagship scientists have taken the art of patterning nanomaterials to the following degree. Specific patterning of Second products is a route to computation and storage making use of Second products, which can produce improved general performance and substantially reduce energy usage than present-day technologies.

1 of the most major the latest discoveries within physics and material technologies is two-dimensional products this kind of as graphene. Graphene is much better, smoother, lighter, and improved at conducting heat and electric power than any other recognized material.

Their most special aspect is maybe their programmability. By making delicate styles in these products, we can transform their houses substantially and perhaps make exactly what we need.

At DTU, scientists have labored on increasing condition of the art for more than a 10 years in patterning Second products, making use of refined lithography machines in the 1500 m2 cleanroom facility. Their operate is centered in DTU’s Middle for Nanostructured Graphene, supported by the Danish Countrywide Study Basis and a aspect of The Graphene Flagship.

The electron beam lithography procedure in DTU Nanolab can create specifics down to ten nanometers. Laptop calculations can predict particularly the condition and dimension of styles in the graphene to generate new sorts of electronics. They can exploit the demand of the electron and quantum houses this kind of as spin or valley levels of freedom, main to high-pace calculations with much much less energy usage. These calculations, nonetheless, request for increased resolution than even the greatest lithography techniques can produce: atomic resolution.

“If we definitely want to unlock the treasure upper body for long term quantum electronics, we need to go beneath ten nanometers and tactic the atomic scale,” claims professor and team chief at DTU Physics, Peter Bøggild.

And that is excactly what the scientists have succeeded in accomplishing.

“We confirmed in 2019 that circular holes positioned with just 12-nanometer spacing transform the semimetallic graphene into a semiconductor. Now we know how to generate circular holes and other designs this kind of as triangles, with nanometer sharp corners. These styles can form electrons centered on their spin and generate crucial elements for spintronics or valleytronics. The method also performs on other Second products. With these supersmall structures, we may generate pretty compact and electrically tunable metalenses to be utilized in high-pace interaction and biotechnology,” points out Peter Bøggild.

Razor-sharp triangle

The analysis was led by postdoc Lene Gammelgaard, an engineering graduate of DTU in 2013 who has because played a essential role in the experimental exploration of Second products at DTU:

“The trick is to spot the nanomaterial hexagonal boron-nitride on top rated of the material you want to pattern. Then you drill holes with a particular etching recipe,” claims Lene Gammelgaard, and continues:

“The etching course of action we designed more than the earlier many years down-dimension styles beneath our electron beam lithography systems’ otherwise unbreakable limit of somewhere around ten nanometers. Suppose we make a circular gap with a diameter of 20 nanometers the gap in the graphene can then be downsized to ten nanometers. Whilst if we make a triangular gap, with the spherical holes coming from the lithography procedure, the downsizing will make a lesser triangle with self-sharpened corners. Typically, styles get more imperfect when you make them lesser. This is the reverse, and this enables us to recreate the structures the theoretical predictions tell us are optimum.”

1 can e.g. generate flat digital meta-lenses — a sort of super-compact optical lens that can be managed electrically at pretty high frequencies, and which in accordance to Lene Gammelgaard can become crucial elements for the interaction technologies and biotechnology of the long term.

Pushing the restrictions

The other critical particular person is a youthful university student, Dorte Danielsen. She received intrigued in nanophysics right after a 9th-quality internship in 2012, received a spot in the final of a countrywide science competitiveness for high college students in 2014, and pursued scientific tests in Physics and Nanotechnology under DTU’s honors method for elite students.

She points out that the system powering the “super-resolution” structures is nonetheless not properly understood:

“We have quite a few possible explanations for this sudden etching habits, but there is nonetheless substantially we don’t have an understanding of. Nonetheless, it is an remarkable and highly valuable method for us. At the exact time, it is fantastic information for the countless numbers of scientists close to the entire world pushing the restrictions for Second nanoelectronics and nanophotonics.”

Supported by the Unbiased Study Fund Denmark, within the METATUNE task, Dorte Danielsen will proceed her operate on incredibly sharp nanostructures. Listed here, the technologies she served produce, will be utilized to generate and investigate optical metalenses that can be tuned electrically.