  Two-dimensional transition metal dichalcogenides (TMDs) provide an attractive
platform for studying strain dependent exciton transport at room temperature
due to large exciton binding energy and strong bandgap sensitivity to
mechanical stimuli. Here, we use Rayleigh type surface acoustic wave (SAW) to
demonstrate controlled and directional exciton transport under weak coupling
regime at room temperature. We screen the in-plane piezoelectric field using
photogenerated carriers to study transport under type-I bandgap modulation and
measure a maximum exciton drift velocity of 600 m/s. Furthermore, we
demonstrate precise steering of exciton flux by controlling the relative phase
between the input RF excitation and exciton photogeneration. The results
provide important insight into the weak coupling regime between dynamic strain
wave and room temperature excitons in a 2D semiconductor system and pave way to
exciting applications of excitonic devices in data communication and
processing, sensing and energy conversion.
