Direct Measurement of the Tunable Electronic Structure of Bilayer MoS2 by Interlayer Twist

• DOI: 10.1021/acs.nanolett.5b03883
• Publication Date: 2016-01-13T15:59:37Z
• Authors: Po-Chun Yeh; Wencan Jin; Nader Zaki; Jens Kunstmann; Daniel Chenet; Ghidewon Arefe; Jerzy T. Sadowski; Jerry I. Dadap; Peter Sutter; James Hone; Richard M. Osgood
• Keywords: Brillouin zone

Using angle-resolved photoemission on micrometer-scale sample areas, we directly measure the interlayer twist angle-dependent electronic band structure of bilayer molybdenum-disulfide (MoS2). Our measurements, performed arbitrarily stacked MoS2 flakes prepared by chemical vapor deposition, provide direct evidence for a downshift quasiparticle energy valence at Brillouin zone center (Γ̅ point) with angle, up to maximum 120 meV angle ∼40°. measurements enable extraction hole effective mass as function angle. While our results Γ̅ agree recently published photoluminescence data, spectrum over full 2D reveal richer and more complicated change in than previously theoretically predicted. The reported here, including evolution twist-angle, new insight into physics twisted transition-metal dichalcogenide bilayers serve guide practical design optoelectronic spin-/valley-tronic devices.