In an international/multi-institutional undertaking, Prof. Tony Low from ECE and researchers from other institutions have conducted a study that highlights how manipulation of 2D materials could make our modern day devices faster, smaller, and better. The findings are published in the most recent edition of Nature Materials, a leading journal in materials science and engineering research.
Two-dimensional materials are a class of nanomaterials that are only a few atoms in thickness. Electrons in these materials are free to move in the two-dimensional plane, but their restricted motion in the third direction is governed by quantum mechanics. Research on these nanomaterials is still in its infancy, but 2D materials such as graphene, transition metal dichalcogenides, and black phosphorus have attracted attention from scientists and engineers for their potential to improve electronic and photonic devices.
In this study, researchers from the University of Minnesota, MIT, Stanford, U.S. Naval Research Laboratory, IBM, and universities in Brazil, UK and Spain, teamed up to present a state-of-the-art review that unifies understanding, for the scientific community, of light-matter interactions in 2D materials, and explores possibilities for future research. They discuss how polaritons, a class of quasiparticles formed through the coupling of photons with electric charge dipoles in solid, allow researchers to marry the speed of photons to the small size of electrons.
“With our devices, we want speed, efficiency, and we want small. Polaritons could offer the answer,” said Tony Low, a professor at the University of Minnesota with the Department of Electrical and Computer Engineering. He is also the lead author of the study.
By exciting the polaritons in 2D materials, electromagnetic energy can be focused down to a volume a million times smaller compared to when it’s propagating in free space.
“Layered two-dimensional materials have emerged as a fantastic toolbox for nano-photonics and nano-optoelectronics, providing tailored design and tunability for properties that are not possible to realize with conventional materials,” said Frank Koppens, group leader at the Institute of Photonic Sciences at Barcelona, Spain, and co-author of the study. “This will offer tremendous opportunities for applications.”
Pointing out the potential applications, Phaedon Avouris, IBM Fellow at the IBM T. J. Watson Research Center and co-author of the paper says, “For example, an atomic layer material like graphene extends the field of plasmonics to the infrared and terahertz regions of the electromagnetic spectrum allowing unique applications ranging from sensing and fingerprinting minute amounts of biomolecules, to applications in optical communications, energy harvesting and security imaging.”
The new study also examined the possibilities of combining 2D materials; combining these materials could create new materials that may have the best qualities of both.
To read the full research paper, entitled “Polaritons in layered two-dimensional materials,” visit the Nature Materials website.