Strong interlayer hybridization in the aligned SnS2/WSe2 hetero-bilayer structure

• DOI: 10.1038/s41699-019-0109-3
• Publication Date: 2019-07-24T13:07:35Z
• Authors: Jihene Zribi; Lama Khalil; Biyuan Zheng; José Avila; Debora Pierucci; Thibault Brulé; Julien Chaste; Emmanuel Lhuillier; Maria C. Asensio; Anlian Pan; Abdelkarim Ouerghi
• Keywords: [PHYS]Physics [physics]; Two-dimensional (2D) materials; 02 engineering and technology; [PHYS.COND]Physics [physics]/Condensed Matter [cond-mat]; 0210 nano-technology; [PHYS.COND] Physics [physics]/Condensed Matter [cond-mat]; SnS2/WSe2; [PHYS] Physics [physics]

AbstractThe combination of monolayers of different two-dimensional (2D) materials into van der Waals hetero-bilayer structures creates unprecedented physical phenomena, acting as a powerful tool for future devices. Understanding and exploiting these phenomena hinge on knowing the electronic structure and the hybridization of hetero-bilayer structures. Here, we show strong hybridization effects arising between the constitutive single layers of a SnS2/WSe2 hetero-bilayer structure grown by chemical vapor deposition. Surprisingly, the valence band maximum position of WSe2 is moved from the K point for the single layer WSe2 to the Γ point for the aligned SnS2/WSe2 hetero-bilayer. Additionally, a significant photoluminescence quenching is observed for the SnS2/WSe2 hetero-bilayer structure with respect to the WSe2 monolayer. Using photoluminescence spectroscopy and nano-angle-resolved photoemission spectroscopy techniques, we demonstrate that the SnS2/WSe2 heterostructure present a type-II band alignment. These findings directly answer many outstanding questions about the electronic band structure and the band offset of SnS2/WSe2 hetero-bilayers for envisaging their applications in nanoelectronics.