Figure 3: Berry phase and topological quantization.
From: Fractional quantum Hall effect in the absence of Landau levels
The total Berry phase as a function of Nmesh/Ntot, which measures the ratio of the area in the boundary phase space for (a) 1/3 filling at Ns=30; (b) 1/5 filling at Ns=40. In fractional quantum Hall phase, a linear curve is observed whose slope is determined by filling factor, as expected. In the Fermi-liquid phase, we observed large fluctuation and non-universal behaviours, indicating the absence of the topological quantization.
