Fig. 8.

a, b Ferromagnetism in an atomically thin Fe₃GeTe₂ (FGT) flake modulated by an ionic gate. a Conductance as a function of the gate voltage Vg measured in a trilayer FGT device at room temperature. The inset shows a schematic of the FGT device structure. b Phase diagram of the trilayer FGT sample as the gate voltage and temperature are varied [99]. c Schematic of the orbital-dependent interlayer super-super-exchange interactions in CrI₃ [167]. d, e 2D CrI₃ field-effect devices. d A schematic side view of a dual-gate bilayer CrI₃ field-effect device. e Magnetic circular dichroism versus magnetic field at three representative doping levels at 4 k (top panel) and 50 K (bottom panel) [163]. f Gate-controlled spin valve signal at room temperature [135]. g Schematic of the magnetic proximity effect for encapsulated graphene with a transparent 1D edge contact to a ferromagnetic electrode [173]. h A Y-shaped graphene spin current demultiplexer with gate voltages $V_{\mathrm{G},i}$ for voltage control of pure spin currents [175].

Figures reproduced with permission from Refs. [99, 135, 163, 167, 173, 175]