Science Daily October 26, 2023
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. Researchers at Columbia University used Re6Se8Cl2, a superatomic semiconductor, to demonstrate the formation of acoustic exciton-polarons. They directly imaged polaron transport in Re6Se8Cl2 at room temperature, revealing quasi-ballistic, wavelike propagation sustained for a nanosecond and several micrometers. Shielded polaron transport led to electronic energy propagation lengths orders of magnitude greater than in other vdW semiconductors, exceeding even silicon over a nanosecond. According to the researchers quasi-flat electronic bands and strong exciton–acoustic phonon coupling are responsible for the transport properties of Re6Se8Cl2, establishing a path to ballistic room-temperature semiconductors… read more. TECHNICAL ARTICLE
… Unimpeded by other phonons along the way, acoustic exciton-polarons in Re6Se8Cl2 ultimately move faster than electrons in silicon… Credit: Jack Tulyag, Columbia University