• Anomalous electrical transport in orientationally controlled trinary hybrids of graphene and twisted bilayer molybdenum disulphide

• # Fulltext

https://www.ias.ac.in/article/fulltext/boms/044/0280

• # Keywords

Graphene; transition metal dichalcogenide; heterostructure; flatbands; moiré superlattice.

• # Abstract

Moiré superlattices of two-dimensional (2D) materials oriented at low twist angles generate a large-scale interference pattern leading to strong interlayer coupling, which influences the band structure and introduces flatbands.Conventional electronic transport measurements have shown the effects of flatband physics, manifesting as correlated insulating states and emergent superconductivity. In this study, we probe the electronic states in a trinary hybrid of graphene and twisted bilayer (tbl) MoS$_2$. Graphene acts as a sensing layer, which captures the electronic effects of the underlying substrate, and we observe certain anomalies in the electronic characteristics of graphene only in the presenceof an underlying 58.5°tbl MoS$_2$, at low temperatures. Interestingly, graphene on tbl MoS$_2$, with twist angle near 0°or on natural bilayer MoS$_2$, does not show any anomalies. Density functional theory calculations show several distinguishablepeaks in the density of states at the conduction band edge of twisted MoS2 near 60°. We speculate that the anomaly appears due to fermi level pinning of graphene owing to a large density of states in the flatbands of twisted bilayer MoS$_2$. An analysis of the energetics in the graphene-MoS$_2$ hybrid quantitatively agree with theoretical predictions.

• # Author Affiliations

1. Department of Physics, Indian Institute of Science, Bangalore 560012, India
2. Centre for Nano Science and Engineering, Indian Institute of Science, Bangalore 560012, India

• # Bulletin of Materials Science

Volume 45, 2022
All articles
Continuous Article Publishing mode

• # Dr Shanti Swarup Bhatnagar for Science and Technology

Posted on October 12, 2020

Prof. Subi Jacob George — Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bengaluru
Chemical Sciences 2020