Robust Excitons and Trions in Monolayer MoTe2

Abstract

Molybdenum telluride (MoTe2) has emerged as a special member in the family of two-dimensional transition metal dichalcogenide semiconductors, owing to the strong spin-orbit coupling and relatively small energy gap, which offers new applications in valleytronic and excitonic devices. Here we successfully demonstrated the electrical modulation of negatively charged (X-), neutral (X0), and positively charged (X+) excitons in monolayer MoTe2 via photoluminescence spectroscopy. The binding energies of X+ and X- were measured to be -24 and -27 meV, respectively.The exciton binding energy of monolayer MoTe2 was measured to be 0.58 ± 0.08 eV via photoluminescence excitation spectroscopy, which matches well with our calculated value of 0.64 eV. Show more