Lattice Reconstruction in MoSe<sub>2</sub>–WSe<sub>2</sub> Heterobilayers Synthesized by Chemical Vapor Deposition
Zhijie Li, Farsane Tabataba‐Vakili, Shen Zhao, Anna Rupp, Ismail Bilgin, Ziria Herdegen, Benjamin März, Kenji Watanabe, Takashi Taniguchi, Gabriel R. Schleder, Anvar S. Baimuratov, Efthimios Kaxiras, Knut Müller‐Caspary, Alexander Högele
Abstract
High Resolution Image Download MS PowerPoint Slide Vertical van der Waals heterostructures of semiconducting transition metal dichalcogenides realize moiré systems with rich correlated electron phases and moiré exciton phenomena. For material combinations with small lattice mismatch and twist angles as in MoSe 2 –WSe 2, however, lattice reconstruction eliminates the canonical moiré pattern and instead gives rise to arrays of periodically reconstructed nanoscale domains and mesoscopically extended areas of one atomic registry. Here, we elucidate the role of atomic reconstruction in MoSe 2 –WSe 2 heterostructures synthesized by chemical vapor deposition. With complementary imaging down to the atomic scale, simulations, and optical spectroscopy methods, we identify the coexistence of moiré-type cores and extended moiré-free regions in heterostacks with parallel and antiparallel alignment. Our work highlights the potential of chemical vapor deposition for applications requiring laterally extended heterosystems of one atomic registry or exciton-confining heterostack arrays.