Fractional quantum Hall effect in a quantum point contact at filling fraction 5/2

摘要: Recent theories suggest that the quasiparticles populate certain quantum Hall states should exhibit exotic braiding statistics could be used to build topological gates. Confined systems support such at a filling fraction ν=5/2 are of particular interest for testing these predictions. Here, we report transport measurements just system, which consists point contact (QPC) in two-dimensional GaAs/AlGaAs electron gas itself exhibits well-developed fractional effect bulk νbulk=5/2. We observe plateau-like features an effective νQPC=5/2 lithographic widths 1.2 μm and 0.8 μm, but not 0.5 μm. Transport near QPCs is consistent with picture chiral Luttinger-liquid edge inter-edge tunnelling, suggesting incompressible state forms this confined geometry.