Fractional quantum Hall state at ν=7/11 , a candidate filling factor for unconventional correlations

Landau flat bands provide a unique setting in which strong Coulomb interactions stabilize exotic correlated ground states that are absent in other flat-band systems. We report the observation of topological protection at filling factor ν=7/11  in a high-mobility two-dimensional electron gas. This fractional quantum Hall state is the particle–hole counterpart of ν=4/11, long regarded as a promising candidate for unconventional correlation physics. Our results demonstrate ν=7/11 as a distinct realization of an unusual fractional quantum Hall phase, thereby enlarging the parameter space in which nonstandard correlations can be investigated. Furthermore, near ν=7/11, at filling factors ν=11/17, 5/8 and 8/13 our data show local minima in the longitudinal resistance but do not display evidence of topological protection.