Extended Data Fig. 7: Dual gate maps at high magnetic fields and Landau fan at high electric field for filling factor assignment of the 2.6° device.
From: Ferromagnetism and topology of the higher flat band in a fractional Chern insulator
a, b, c, Longitudinal resistance Rxx as a function of filling factor ν and electric field D/ε0 at out-of-plane magnetic fields (μ0H) of 7 T (a), 9 T (b), and 13 T (c). The regions in black are inaccessible due to their high resistance. A resistive state at ν = -3/2 is visible near D/ε0 = 0. d, Linecuts of Rxx at selected magnetic fields. Each curve is displaced by 10 kΩ for clarity and the arrow highlights the non-dispersing resistive maximum at the v = -3/2 state. e, The Landau fan of Rxx measured as a function of ν and μ0H at a finite electric field of D/ε0 = 190 mV/nm, denoted as the white line in a. Clear quantum oscillations are visible stemming from the filling factor of ν = -3 and ν = -1, which allows accurate filling factor assignment for the main figures. The degeneracy of the Landau levels is denoted on the top axis. Data are taken at a temperature of 15 mK.
