Room temperature wavelike exciton transport in a van der Waals superatomic semiconductor

• Main Authors: Tulyagankhodjaev, Jakhangirkhodja A, Shih, Petra, Yu, Jessica, Russell, Jake C, Chica, Daniel G, Reynoso, Michelle E, Su, Haowen, Stenor, Athena C, Roy, Xavier, Berkelbach, Timothy C, Delor, Milan
• Format: Journal Article
• Language: English
• Published: 13-06-2023
• Subjects: Physics - Materials Science
• DOI: 10.48550/arxiv.2306.07808

Science, 2023, vol. 382, pp. 438-442 The transport of energy and information in semiconductors is limited by
scattering between electronic carriers and lattice phonons, resulting in
diffusive and lossy transport that curtails all semiconductor technologies.
Using Re6Se8Cl2, a van der Waals (vdW) superatomic semiconductor, we
demonstrate the formation of acoustic exciton-polarons, an electronic
quasiparticle shielded from phonon scattering. We directly image polaron
transport in Re6Se8Cl2 at room temperature and reveal quasi-ballistic, wavelike
propagation sustained for nanoseconds and several microns. Shielded polaron
transport leads to electronic energy propagation orders of magnitude greater
than in other vdW semiconductors, exceeding even silicon over nanoseconds. We
propose that, counterintuitively, quasi-flat electronic bands and strong
exciton-acoustic phonon coupling are together responsible for the remarkable
transport properties of Re6Se8Cl2, establishing a new path to ballistic
room-temperature semiconductors.