Fig. 2: Ionic gating illustration on Co_1/3TaS₂ nanoflakes and manipulation mechanism of quantum 3Q phase.

a Hall measurement schematic of a gating device, while the gate voltage was applied from the side gate pad to the drain. b Optical image of a typical gating device of Co_1/3TaS₂ nanoflake. c, d Gating mechanism illustration of ionic gating. A positive gate voltage causes the intercalation of lithium ions passing through the material, inducing electron doping. In contrast, the negative voltage accumulates the ClO₄^- ions, depleting electrons and introducing hole doping, which diffuses throughout the system. e Phase diagram of Co_1/3TaS₂ (adapted from a very recent work³⁶) and corresponding schematic of electron/hole doping. The colour plot of the Hall conductivity in Co_xTaS₂ bulk crystals constructs the magnetic phase diagram, which comprises four distinct phases: Paramagnetic, Single-Q (1Q), Triple-Q (3Q), and Helical phases. The anomalous Hall effect originates from the scalar spin chirality in 3Q phase states and varies with Co concentration. The red pointers indicate four kinds of gating samples with different Co concentrations. In our experiments, the orange arrows schematically indicate the gating regions by positive and negative voltages.