Orbitally Tuned Composite-Fermion Pairing Transitions in Bilayer Graphene
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Updated: Nov 2, 2026

Optimized Fabrication Procedure for High-Quality Graphene-based Moiré Superlattice Devices
Published on: July 11, 2025
Ravi Kumar1, Tomer Firon1, André Haug1
1Weizmann Institute of Science, Department of Condensed Matter Physics, Rehovot 76100, Israel.
Abstract:
The effective interaction between composite fermions, set entirely by the Coulomb potential and the underlying electronic Landau level orbitals, can stabilize exotic fractional quantum Hall states. In particular, half-filled Landau levels with different orbital character can host either metallic or paired phases of composite fermions. Here, we leverage experimental control over the orbital composition to realize a composite-fermion pairing transition in the first excited Landau level of bilayer graphene. Transport measurements at filling factors ν=9/2 and (11/2) reveal conductive states giving way to well-developed plateaus with increasing displacement fields. These states are insensitive to an in-plane magnetic field, indicating single-component ground states and thus pointing at non-Abelian orders. Our numerical study, based on displacement-field-dependent Landau-level wave functions, supports the orbital origin of the pairing transition and suggests Moore-Read or anti-Pfaffian ground states.
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