Research paperExperimental Characterization1/3 Fractional and Gapless Integer Quantum Anomalous Hall States in Rhombohedral GrapheneJackson P. Butler, Tonghang Han, Andrew DiFabbio, Zach Hadjri et al.arXiv preprint·2026·10.1103/physrevlett.133.206504·arXiv:2606.06450AbstractWe report the fractional quantum anomalous Hall effect at moiré filling factor ν = 1/3 in R₅G/hBN moiré superlattice devices, using quantum capacitance and transport measurements. By tuning displacement field, we observe a transition from a 1/3 fractional Chern insulator to a trivial charge density wave state. We extract thermodynamic gaps for fractional states, with the largest at ν = 1/3. We also study ν = 1 and nearby fillings, finding a gapped integer quantum anomalous Hall state and a gapless, highly compressible extended quantum anomalous Hall regime.Read more
R₅G/hBN moiré superlattice device used for penetration-capacitance phase-diagram and thermodynamic-gap measurements.1 characterization3 properties3 figuresExperimentalCStudied MaterialBNSubstrate / DielectricCCapping Or ContactExpand
Second R₅G/hBN device (D₂) used for transport confirmation of the ν = 1/3 FQAH state and related Hall measurements.1 characterization1 figureExperimentalCStudied MaterialBNSubstrate / DielectricCCapping Or ContactExpand
Research paperExperimental Characterization1/3 Fractional and Gapless Integer Quantum Anomalous Hall States in Rhombohedral GrapheneJackson P. Butler, Tonghang Han, Andrew DiFabbio, Zach Hadjri et al.arXiv preprint·2026·10.1103/physrevlett.133.206504·arXiv:2606.06450AbstractWe report the fractional quantum anomalous Hall effect at moiré filling factor ν = 1/3 in R₅G/hBN moiré superlattice devices, using quantum capacitance and transport measurements. By tuning displacement field, we observe a transition from a 1/3 fractional Chern insulator to a trivial charge density wave state. We extract thermodynamic gaps for fractional states, with the largest at ν = 1/3. We also study ν = 1 and nearby fillings, finding a gapped integer quantum anomalous Hall state and a gapless, highly compressible extended quantum anomalous Hall regime.Read more
R₅G/hBN moiré superlattice device used for penetration-capacitance phase-diagram and thermodynamic-gap measurements.1 characterization3 properties3 figuresExperimentalCStudied MaterialBNSubstrate / DielectricCCapping Or ContactExpand
Second R₅G/hBN device (D₂) used for transport confirmation of the ν = 1/3 FQAH state and related Hall measurements.1 characterization1 figureExperimentalCStudied MaterialBNSubstrate / DielectricCCapping Or ContactExpand
Research paperExperimental Characterization1/3 Fractional and Gapless Integer Quantum Anomalous Hall States in Rhombohedral GrapheneJackson P. Butler, Tonghang Han, Andrew DiFabbio, Zach Hadjri et al.arXiv preprint·2026·10.1103/physrevlett.133.206504·arXiv:2606.06450AbstractWe report the fractional quantum anomalous Hall effect at moiré filling factor ν = 1/3 in R₅G/hBN moiré superlattice devices, using quantum capacitance and transport measurements. By tuning displacement field, we observe a transition from a 1/3 fractional Chern insulator to a trivial charge density wave state. We extract thermodynamic gaps for fractional states, with the largest at ν = 1/3. We also study ν = 1 and nearby fillings, finding a gapped integer quantum anomalous Hall state and a gapless, highly compressible extended quantum anomalous Hall regime.Read more
R₅G/hBN moiré superlattice device used for penetration-capacitance phase-diagram and thermodynamic-gap measurements.1 characterization3 properties3 figuresExperimentalCStudied MaterialBNSubstrate / DielectricCCapping Or ContactExpand
Second R₅G/hBN device (D₂) used for transport confirmation of the ν = 1/3 FQAH state and related Hall measurements.1 characterization1 figureExperimentalCStudied MaterialBNSubstrate / DielectricCCapping Or ContactExpand
Research paperExperimental Characterization1/3 Fractional and Gapless Integer Quantum Anomalous Hall States in Rhombohedral GrapheneJackson P. Butler, Tonghang Han, Andrew DiFabbio, Zach Hadjri et al.arXiv preprint·2026·10.1103/physrevlett.133.206504·arXiv:2606.06450AbstractWe report the fractional quantum anomalous Hall effect at moiré filling factor ν = 1/3 in R₅G/hBN moiré superlattice devices, using quantum capacitance and transport measurements. By tuning displacement field, we observe a transition from a 1/3 fractional Chern insulator to a trivial charge density wave state. We extract thermodynamic gaps for fractional states, with the largest at ν = 1/3. We also study ν = 1 and nearby fillings, finding a gapped integer quantum anomalous Hall state and a gapless, highly compressible extended quantum anomalous Hall regime.Read more
R₅G/hBN moiré superlattice device used for penetration-capacitance phase-diagram and thermodynamic-gap measurements.1 characterization3 properties3 figuresExperimentalCStudied MaterialBNSubstrate / DielectricCCapping Or ContactExpand
Second R₅G/hBN device (D₂) used for transport confirmation of the ν = 1/3 FQAH state and related Hall measurements.1 characterization1 figureExperimentalCStudied MaterialBNSubstrate / DielectricCCapping Or ContactExpand