(Invited, Digital Presentation) Ultrathin Lateral Heterostructures Based on Two-Dimensional Semiconductors

Abstract

Low-dimensional (2D) materials, including carbon nanotubes, graphene, boron nitrides, and transition metal dichalcogenides (TMDs), have provided a platform to explore novel physics at the nano-scale. In addition to the fascinating properties of low-dimensional materials themselves, they allow exploring novel superstructures, such as heterojunctions, heterostacks, and superlattices, which give even broader possibilities. We are working on low-dimensional superstructures fabricated by (1) crystal growth with metal-organic chemical vapor deposition (MOCVD) and molecular beam epitaxy (MBE), and (2) stacking each component with the full-dry-transfer-based manipulation technique[1]-[6]. This presentation will focus on our recent works on low-dimensional superstructures, such as 2D ultrathin lateral superlattices. For example, we have successfully realized MoS2/WS2 2D lateral superlattices with a periodicity of down to one-atom-thick by MOCVD with an automatic valve control system. Also, we have observed characteristic PL arising probably from 1D junction structures. More details on the fabrication and optical properties of these superstructures will be addressed in this talk.[1] Y. Murai, et. al., ACS Nano 2021, doi.org/10.1021/ascnano.1c04584 [2] T. Hotta, et. al., ACS Nano 2021, 51:1370-1377.[3] T. Hotta, et al., Phys. Rev. B 2020, 102:115424.[4] S. Zhao et al., Phys. Rev. Lett. 2020, 124:106101.[5] Y. Uchiyama et. al., npj 2D Mater. App. 2019, 3:26.[6] M. Okada, et. al., ACS Nano 2018, 12:2498-2505.