Quasi-1D exciton channels in strain-engineered 2D materials

Strain engineering is a powerful tool in designing artificial platforms for high-temperature excitonic quantum devices. Combining strong light-matter interaction with robust and mobile exciton quasiparticles, two-dimensional transition metal dichalcogenides (2D TMDCs) hold great promise in this endeavor. However, realizing complex excitonic architectures based on strain-induced electronic potentials alone has proven to be exceptionally difficult so far. Here, we demonstrate deterministic strain engineering of both single-particle electronic bandstructure and excitonic many-particle interactions. We create quasi-1D transport channels to confine excitons and simultaneously enhance their mobility through locally suppressed exciton-phonon scattering. Using ultrafast, all-optical injection and time-resolved readout, we realize highly directional exciton flow with up to 100% anisotropy both at cryogenic and room temperatures. The demonstrated fundamental modification of the exciton transport properties in a deterministically strained 2D material with effectively tunable dimensionality has broad implications for both basic solid-state science and emerging technologies.

Automated summary

Strain engineering is used for designing high-temperature excitonic quantum devices by manipulating the electronic bandstructure and many-particle interactions of 2D TMDCs. The research demonstrates a deterministic way to confine and enhance the mobility of excitons, leading to highly directional exciton flow with significant anisotropy. This fundamental modification in the transport properties of excitons in deterministically strained 2D materials has broad implications for both solid-state science and emerging technologies.