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Archivio digitale delle tesi discusse presso l’Università di Pisa

Tesi etd-06202022-191631


Tipo di tesi
Tesi di laurea magistrale
Autore
DI LUCA, MARIO
URN
etd-06202022-191631
Titolo
Visualization of non-identical moiré twins in bilayer graphene ​
Dipartimento
FISICA
Corso di studi
FISICA
Relatori
relatore Dott.ssa Ribeiro-Palau, Rebeca
relatore Prof. Roddaro, Stefano
Parole chiave
  • electronis transport
  • graphene
  • twistronics
  • two-dimensional materials
  • van der Waals heterostructures
Data inizio appello
21/07/2022
Consultabilità
Completa
Riassunto
The discovery and isolation of new two-dimensional materials, such as hexagonal boron nitride (hBN) and graphene, have led to the development of new artificial materials called van der Waals heterostructures (vdW). Such materials introduce a new degree of freedom that can be controlled to modify the physical properties of the vdW heterostructures; the relative angle alignment between different layers. In this project, our objective is to investigate the effect of different angular alignments in bilayer graphene/hBN heterostructures. To directly link the electronic properties of the vdW heterostructure to the alignment angle, we will use a twistable device in which it is possible to rotate the hBN using the tip of an Atomic Force Microscope. In bilayer graphene aligned with boron nitride, it has been highlighted the existence of two non-identical moiré twins when the two layers are aligned at 0°or 60°. This thesis shows an even more surprising difference in room-temperature transport measurements that indicates a clear difference in the band structures. Moreover, I will highlight the differences between the band structures of non-identical moiré twins using low-temperature magnetotransport measurements, AFM and Raman measurements.
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