Unconventional fractional quantum Hall effect in monolayer and bilayer graphene
نویسندگان
چکیده
The commensurability condition is applied to determine the hierarchy of fractional fillings of Landau levels in monolayer and in bilayer graphene. The filling rates for fractional quantum Hall effect (FQHE) in graphene are found in the first three Landau levels in one-to-one agreement with the experimental data. The presence of even denominator filling fractions in the hierarchy for FQHE in bilayer graphene is explained. Experimentally observed hierarchy of FQHE in the first and second Landau levels in monolayer graphene and in the zeroth Landau level in bilayer graphene is beyond the conventional composite fermion interpretation but fits to the presented nonlocal topology commensurability condition.
منابع مشابه
Fractional quantum Hall effect in multicomponent systems THÈSE
We study a number of fractional quantum Hall systems, such as quantum Hall bilayers, wide quantum wells or graphene, where underlying multicomponent degrees of freedom lead to the novel physical phenomena. In the quantum Hall bilayer at the filling factor ν = 1 we study mixed composite boson-composite fermion trial wave functions in order to describe the disordering of the exciton superfluid as...
متن کاملRobust fractional quantum Hall effect in the N=2 Landau level in bilayer graphene
The fractional quantum Hall effect is a canonical example of electron-electron interactions producing new ground states in many-body systems. Most fractional quantum Hall studies have focussed on the lowest Landau level, whose fractional states are successfully explained by the composite fermion model. In the widely studied GaAs-based system, the composite fermion picture is thought to become u...
متن کاملBand topology and quantum spin Hall effect in bilayer graphene
We consider bilayer graphene in the presence of spin orbit coupling, to assess its behavior as a topological insulator. The first Chern number n for the energy bands of single and bilayer graphene is computed and compared. It is shown that for a given valley and spin, n in a bilayer is doubled with respect to the monolayer. This implies that bilayer graphene will have twice as many edge states ...
متن کاملQuantum Hall effect in graphene: Status and prospects
Graphene is the recently discovered two-dimensional (2D) one atom thick allotrope of carbon. Electrons in graphene, obeying a linear dispersion relation, behave like massless relativistic particles. It is a 2D nanomaterial with many peculiar properties. It is the thinnest material in the universe and the strongest ever measured. Its charge carriers exhibit intrinsic mobility and can travel micr...
متن کامل