Twistronics: A Recent Avenue in van der Waals Heterostructures
Pramoda K. Nayak
Department of Physics and Materials Science Research Centre, Indian Institute of Technology Madras,
Chennai 600036, India.
After the discovery of graphene, the most prominent representative class of two-dimensional (2D) layered materials, many other 2D crystals have been identified, often with intriguing properties that have no counterparts in three-dimensional solids. Even if individual 2D materials own various interesting and unexpected properties, the stacking of such layers leads to ‘artificial vdW solids’ called as van der Waals heterostructures (vdW HSs) that result in the emergence of new states of matter with novel functionalities.The vdW HSs not only depend on the combination of different 2D crystal but also on their rotational alignment opening the avenue for a new field called twisttronics. Coupling between the two layers depends on the stacking angle, which can be used as an external degree of freedom to tune their optical and electronic properties. In this talk, I will cover the atlas of vdW materials and their heterostructures emphasizing on synthesis, characterization and potential applications in electronics and optoelectronics. Additionally, I will describe how a simple twist can dramatically changes the functionalities of vdW HSs, fabricated from 2D monolayers grown by chemical vapor deposition. Finally, I will summarize the current challenges and future opportunities in this emerging field.