Endre Tóvári (Budapest University of Technology and Economics)

Electrostatic confinement in monolayer graphene

Graphene is a promising material for spintronics and quantum computing applications due to its micron-scale spin coherence length. To create large-scale devices, it is of paramount importance to design the whole structure from graphene, so tunable quantum dots are needed.
However, electrostatic confinement in single-layer graphene cannot be achieved due to the linear band structure: a charge may tunnel through a potential barrier with unit probability (Klein tunnelling).
At high magnetic fields, in the quantum Hall regime, Landau levels form, creating band gaps and edge states. Conductance oscillations have been observed in multiple suspended two-terminal devices, originating in single quantum dots, which were induced by the remanent disorder’s potential. A quantum dot’s presence in the conductance could be observed since it was acting as a scattering center between the quantum Hall edge states, or the contacts.

Comments are closed.