Observation of 1/3 fractional quantum Hall physics in balanced large angle twisted bilayer graphene

Abstract

Magnetotransport of conventional semiconductor based double layer systems with barrier suppressed interlayer tunneling has been a rewarding subject due to the emergence of an interlayer coherent state that behaves as an excitonic superfluid. Large angle twisted bilayer graphene offers unprecedented strong interlayer Coulomb interaction, since both layer thickness and layer spacing are of atomic scale and a barrier is no more needed as the twist induced momentum mismatch suppresses tunneling. The extra valley degree of freedom also adds richness. Here we report the observation of fractional quantum Hall physics at 1/3 total filling for balanced layer population in this system. Monte Carlo simulations support that the ground state is also an excitonic superfluid but the excitons are composed of fractional rather than elementary charges. The observed phase transitions with an applied displacement field at this and other fractional fillings are also addressed with simulations. They reveal ground states with different topology and symmetry properties.

accepted to Nature communications

References in corpus (5)

• Spinful Composite Fermions in a Negative Effective Field
• Abelian and Non-Abelian States in $\nu =2/3$ Bilayer Fractional Quantum Hall Systems
• Competing Abelian and non-Abelian topological orders in $\nu =1/3+1/3$ quantum Hall bilayers
• Theoretical phase diagram of two-component composite fermions in double layer graphene
• Orbitally controlled quantum Hall states in decoupled two-bilayer graphene sheets

Cited by in corpus (1)

• Optical signatures of -1/3 fractional quantum anomalous Hall state in twisted MoTe2