Density-Functional Tight-Binding Simulations of Curvature-Controlled Layer Decoupling and Band-Gap Tuning in Bilayer MoS2
Koskinen, P., Fampiou, I., & Ramasubramaniam, A. (2014). Density-Functional Tight-Binding Simulations of Curvature-Controlled Layer Decoupling and Band-Gap Tuning in Bilayer MoS2. Physical review letters, 112(18), Article 186802. https://doi.org/10.1103/PhysRevLett.112.186802
Published inPhysical review letters
© 2014 American Physical Society. Published in this repository with the kind permission of the publisher.
Monolayer transition-metal dichalcogenides (TMDCs) display valley-selective circular dichroism due to the presence of time-reversal symmetry and the absence of inversion symmetry, making them promising candidates for valleytronics. In contrast, in bilayer TMDCs both symmetries are present and these desirable valley-selective properties are lost. Here, by using density-functional tight-binding electronic structure simulations and revised periodic boundary conditions, we show that bending of bilayer MoS2 sheets breaks band degeneracies and localizes states on separate layers due to bendinginduced strain gradients across the sheets. We propose a strategy for employing bending deformations in bilayer TMDCs as a simple yet effective means of dynamically and reversibly tuning their band gaps while simultaneously tuning valley-selective physics.
PublisherAmerican Physical Society
Publication in research information system
MetadataShow full item record
Showing items with similar title or keywords.
Nokelainen, Johannes (2014)Boorinitridin (BN) nanorakenteet ovat sekä rakenteellisesti että lujuusominaisuuksiensa puolesta hyvin samankaltaisia vastaavien hiilirakenteiden kanssa. Suurimpana erona on BN:n sähköinen eristävyys kun taas hiilirakenteet ...
Shi, Hongbo; Koskinen, Pekka; Ramasubramaniam, Ashwin (American Chemical Society, 2017)We present a self-consistent charge density-functional tight-binding (SCC-DFTB) parametrization for PtRu alloys, which is developed by employing a training set of alloy cluster energies and forces obtained from Kohn–Sham ...
Levämäki, H.; Kuisma, Mikael; Kokko, K. (AIP Publishing LLC, 2019)We implement a Becke fuzzy cells type space partitioning scheme for the purposes of exchange-correlation within the GPAW projector augmented-wave method based density functional theory code. Space partitioning is needed ...
Pihlajamäki, Antti (2018)Single-layer black phosphorus or phosphorene is a two-dimensional material made from a puckered honeycomb structure. It is a semiconductor with a tunable band gap and both its mechanical and electronic properties are highly ...
Ukkola, Eerik (2020)Borophene is a recently discovered two-dimensional allotrope of boron that hasshown unique electromechanical properties. In this study mechanical properties ofborophene are modeled with density-functional tight-binding ...