Leslie Schoop a Schmidt Transformative Technology Fund awardee

Professor of Chemistry Leslie Schoop has been awarded funding through the Eric and Wendy Schmidt Transformative Technology Fund for a collaboration with Professor of Physics B. Andrei Bernevig, one of eight supported projects announced by the University this week.

Their proposal, “Accelerating Twistable Quantum Materials Design,” was chosen for its potential to make bold, transformational contributions in the natural sciences and engineering.

In this fundamental research, Schoop and Bernevig seek to advance an emerging field in stacked, two-dimensional materials called twistronics that yields exotic properties and quantum phenomena not yet fully understood. Their ultimate goal is to establish Princeton University as the global hub for computational analyses and material growth: a place where researchers worldwide can access comprehensive predictions and calculations and obtain high-quality twisted materials for their experiments.

“In 2018, researchers figured out that if you take one sheet of graphene and you put another on top of it and slightly misalign the angle, slightly twisting it, then many exotic behaviors arise. Since then, the field of twistronics has exploded,” said Schoop. “It’s been done a lot with graphene and some of the transition metals dichalcogenides, but we want to expand on that.

“I’m very happy that we have an opportunity to work on this ambitious project,” she said of the funding. “It wouldn’t have been possible without this support because it is going to require a lot of resources.”

The Eric and Wendy Schmidt Transformative Technology Fund was created in 2009 through a gift from Eric and Wendy Schmidt. Schmidt earned his bachelor’s degree in electrical engineering from Princeton in 1976 and served as a Princeton trustee from 2004 to 2008.

“The research teams supported through the Schmidt fund this year are poised to create powerful new research tools and use AI and machine learning to accelerate discovery,” said Princeton University Dean for Research Peter Schiffer. “The fund enables researchers across disciplines to take big swings, advance ambitious and exciting research, and even build new fields that benefit society.”

What Schoop and Bernevig have in mind is the formation of an AI-guided “library” of twistable materials whose properties could form the basis for interesting electronics and computing, possibly even new routes to superconductivity.

Using artificial intelligence to identify theoretical candidate materials and parse their complex structures, Bernevig will then pass potential candidates along to Schoop. She’ll review them to determine whether they are chemically reasonable and then attempt to grow them into samples that can be shipped for experimental use in labs across the country.

“There are databases that predict possible new materials but often those are just theoretical, and the materials turn out to not be viable,” said Schoop. “We already looked at some first-edition results and came back with some candidates that look good and have interesting new physics, and so now I will grow the materials. Depending on the material, such growth might be quite challenging, but we are excited to start.

“We’re hoping we can start distributing them to experimental collaborators who can exfoliate them to monolayer form and twist them and then measure the properties,” said Schoop. “So far just a few material classes have been covered. We want to keep going and find more. This is an ambitious project.”

To twist a material physically, the monolayer is first sliced with a laser into two homogenous sheets, equally oriented. One of the layers is picked up with a tool that includes a micro-screw, which is turned or twisted infinitesimally before it’s replaced on top of the bottom layer. That misalignment confers the exotic properties.

“You create what is a called Moiré pattern. Now you get areas where the hexagons in the material structure are on top of each other and areas where they are not, where they’re staggered,” said Schoop. “Basically, the orbitals have very different interactions if they have atoms directly on top of each other or if they’re offset into this area. You have a completely new molecular arrangement. It really changes the chemistry. You can create lots and lots of new phases here.

“But this is fundamental. Right now we’re just trying to understand what you can do with the electrons if you put them in uncomfortable positions. We’ve really only just scratched the surface.”

Schoop and Bernevig plan to have a viable catalogue of twistable materials available within a year.

For information on the full list of awardees this year, click here.