Quest for quantum material could benefit from graphene that buckles

Graphene, an extremely thin two-dimensional layer of graphite used in pencils, stretches as it cools when hooked to a flat surface, resulting in beautiful pucker patterns that can benefit the search for new quantum material and superconductors, according to Rutgers-leading research in the journal Nature.

Quantum materials host highly interacting electrons with special properties, such as twisted trajectories, that can provide building blocks for super-fast quantum computers. They can also become superconductors that can reduce energy consumption by making energy transport and electronic devices more efficient.

“The cushioning we discovered in graphene mimics the effect of colossally large magnetic fields unattainable with current magnetic technologies, leading to dramatic changes in the electronic properties of the material,” said lead author Eva Y. Andrei , Board of Governors Professor in the Department of Physics and Astronomy in the School of Arts and Sciences at Rutgers University-New Brunswick. “Cutting rigid thin films such as graphene laminate on flexible materials is gaining ground as a platform for stretchable electronics with many important applications, including eye-like digital cameras, energy harvesters, skin sensors, health monitors such as small robots and intelligent surgical gloves. discovery paves the way for the development of nano-robotic control devices that could one day play a role in biological diagnostics and tissue repair. “

The scientists studied curved graphene crystals whose properties change radically as they cool, and essentially create new materials with electrons that become slower, become aware of each other and interact strongly, creating fascinating phenomena such as superconductivity and magnetism, according to Andrei.

Using high-tech imaging and computer simulations, the scientists showed that graphene placed on a flat surface made of niobium diselenide, buckles when cooled to 4 degrees above absolute zero. At the electrons in graphene, the mountain and valley landscapes created by bending appear as gigantic magnetic fields. These pseudo-magnetic fields are an electronic illusion, but they act as real magnetic fields, according to Andrei.

“Our research proves that cuts in 2-D materials can dramatically change their electronic properties,” she said.

The next steps include developing ways to construct embedded 2-D materials with new electronic and mechanical properties that could be beneficial in nano-robotics and quantum processing, according to Andrei.

The first author is Jinhai Mao, formerly a research fellow in the Department of Physics and Astronomy and now a researcher at the University of Chinese Academy of Sciences.