Hannu-Pekka Komsa

Two-Dimensional Transition Metal Dichalcogenides under Electron Irradiation: Defect Production and Doping

Using first-principles atomistic simulations, we study the response of atomically thin layers of transition metal dichalcogenides (TMDs)--a new class of two-dimensional inorganic materials with unique electronic properties--to electron irradiation. We calculate displacement threshold energies for atoms in 21 different compounds and estimate the corresponding electron energies required to produce defects. For a representative structure of MoS2, we carry out high-resolution transmission electron microscopy experiments and validate our theoretical predictions via observations of vacancy formation under exposure to an 80 keV electron beam. We further show that TMDs can be doped by filling the vacancies created by the electron beam with impurity atoms. Thereby, our results not only shed light on the radiation response of a system with reduced dimensionality, but also suggest new ways for engineering the electronic structure of TMDs.

Electronic structures and optical properties of realistic transition metal dichalcogenide heterostructures from first principles

We calculate from first principles the electronic structure and optical properties of a number of transition metal dichalcogenide (TMD) bilayer heterostructures consisting of MoS

Two-dimensional Transition Metal Dichalcogenide Alloys: Stability and Electronic Properties

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Single-Layer ReS2: Two-Dimensional Semiconductor with Tunable In-Plane Anisotropy

layers sandwiched with WS

Properties of Individual Dopant Atoms in Single‐Layer MoS2: Atomic Structure, Migration, and Enhanced Reactivity

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Atomic scale microstructure and properties of Se-deficient two-dimensional MoSe2.

, MoSe

Three-fold rotational defects in two-dimensional transition metal dichalcogenides

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Atomic structure and dynamic behaviour of truly one-dimensional ionic chains inside ?carbon nanotubes

, MoTe

Comparison of vacancy and antisite defects in GaAs and InGaAs through hybrid functionals

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Experimental Observation of Boron-Nitride Chains

, BN, or graphene sheets. Contrary to previous works, the systems are constructed in such a way that the unstrained lattice constants of the constituent incommensurate monolayers are retained. We find strong interaction between the