Sulfur isotope engineering of exciton and lattice dynamics in MoS2 monolayers

Abstract The optoelectronic properties of two-dimensional (2D) atomically thin transition metal dichalcogenides (TMDCs) are predominantly governed by excitons and their interaction with lattice various physical fields. Therefore, it is essential to understand the role played in light–matter processes. We introduce sulfur isotope engineering for first time TMDC family, which enables us disentangle crucial phonons TMDCs. With gradual introduction heavier isotopes chemical vapor deposition growth M mathvariant="normal">o mathvariant="normal">S 2 , we discovered a systematic variation phonon energy. Consequently, transient steady-state spontaneous photoluminescence spectra were dramatically altered. Accordingly, isotopically pure monolayers (MLs) show more intrinsic enhanced emission efficiencies than mixed MLs. free exciton energies temperature modified MLs can be well described Varshini’s equation. Along enormous significance practical applications, our study provides unique platform fundamentals optical processes 2D systems, where lattice-related quasi-particles play dominant role.