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arXiv · 2004.14202

High phonon-limited mobility of charged and neutral excitons in mono- and bilayer MoTe2

Sophia Helmrich·Alexander W. Achtstein·Hery Ahmad·Matthias Kunz·Bastian Herzog·Oliver Schoeps·Ulrike Woggon·Nina Owschimikow
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Abstract

We analyze the lineshape of the quasiparticle photoluminescence of monolayer and bilayer molybdenum ditelluride in temperature- and excitation intensity-dependent experiments. We confirm the existence of a negatively charged trion in the bilayer 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, with the mobilities showing the highest values so far reported for transition metal dichalcogenides.

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Sophia Helmrich, Alexander W. Achtstein, Hery Ahmad, Matthias Kunz, Bastian Herzog, Oliver Schoeps, Ulrike Woggon, Nina Owschimikow. 2020-04-29. High phonon-limited mobility of charged and neutral excitons in mono- and bilayer MoTe2. https://arxiv.org/abs/2004.14202

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