Towards straintronics: Guiding excitons in 2D supplies

From a workforce of City College of New York physicists and their collaborators in Japan and Germany comes one other development within the examine of excitons—electrically impartial quasiparticles that exist in insulators, semi-conductors and a few liquids. The researchers have created an “excitonic” wire, or one-dimensional channel for excitons. This ensuing units may one day substitute sure duties that are actually carried out by commonplace transistor know-how.

Florian Dirnberger, post-doc in Vinod Menon’s analysis group in CCNY’s Center for Discovery and Innovation, and one of many lead authors of the examine that seems within the journal Science Advances, detailed the workforce’s breakthrough. “Our main achievement was to manage to create these excitonic wires, essentially one-dimensional channels for excitons in what is otherwise a two-dimensional semiconductor,” he mentioned. “Since charge-neutral excitons are not simply controlled by external voltages, we had to rely on a different approach. By depositing the atomically thin 2D crystal on top of a microscopically small wire, a thousand times thinner than a human hair, we created a small, elongated dent in the two-dimensional material, slightly pulling apart the atoms in the two-dimensional crystal and inducing strain in the material. For excitons, this dent is much like a pipe for water and once trapped inside, they are bound to move along the pipe, realizing quasi one-dimensional transport of excitons.”

This development holds prospects for brand new units.

“Manipulating the motion of excitons at the nanoscale realizes an important step towards excitonic devices,” famous Dirnberger. “Platforms based on two-dimensional semiconductor transition-metal dichalcogenides offer an interesting new approach called straintronics.”

Possible outcomes embrace progressive units based mostly on excitons that function at room temperature and will substitute sure duties carried out by up to date transistor know-how.