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arXiv · 2408.08354

Phase diagram of compressible and paired states in the quarter-filled Landau level

Misha Yutushui·David F. Mross
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Abstract

Quantum Hall plateaus at quarter fillings occur in GaAs wide quantum wells, hole-doped GaAs, and bilayer graphene. However, the interactions favoring incompressible states over compressible composite-Fermi liquids at such fillings are not well understood. We devise a method of computing the trial energies for Haldane pseudopotentials via Monte Carlo sampling. Applying it to the quarter-filled lowest Landau level, we find that tuning the third and fifth pseudopotential can stabilize anti-Pfaffian, Moore-Read, and f-wave states. The smallest deviations from pure Coulomb interactions are required by anti-Pfaffian, whose presence is indicated by daughter states in recent experiments of bilayer graphene at $\nu=\frac{3}{4}$.

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Misha Yutushui, David F. Mross. 2024-08-15. Phase diagram of compressible and paired states in the quarter-filled Landau level. https://doi.org/10.1103/physrevb.111.035106

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