High Phonon-Limited Mobility Of Charged And Neutral Excitons In Mono- And Bilayer Mote2

We analyze the lineshape of the quasiparticle photoluminescence of monolayer (ML) and bilayer (BL) molybdenum ditelluride in temperature- and excitation intensity-dependent experiments. We confirm the existence of a negatively charged trion in the BL based on its emission characteristics and find hints for a coexistence of intra- and interlayer trions with a few meV splitting in energy. From the lineshape analysis of exciton and trion emission we extract values for exciton and trion deformation potentials as well as acoustical and optical phonon-limited mobilities in MoTe2. We estimate an acoustical phonon limited mobility of 6000 and 4300 cm(2) Vs(-1) for the exciton at low temperature for ML and BL, respectively, which corresponds to an electron mobility of 10(5) cm(2) Vs(-1). At higher temperatures, the optical phonons limit the mobility to 1100 and 250 cm(2) Vs(-1) for ML and BL.