Active control of chiroptical responses in metasurfaces is critical for advancing photonic spin-selective technologies. Here, we propose and experimentally demonstrate a multifunctional chiral metasurface based on the phase-change material of vanadium dioxide (${\mathrm{VO}}_2$) that offers triple-state switching in circular dichroism. Dual channels of external electric voltages were adopted to independently drive the phase transition of two respective ${\mathrm{VO}}_2$ islands in a planar metasurface unit, where the selective control on the left-handed chiral, right-handed chiral, and achiral responses was experimentally achieved. Our method enables discrete switching between positive, zero, and negative chirality, as well as continuous circular dichroism strength tuning, surpassing the conventional single chiral state modulation. Such a dual-channel control method offers an easy pathway toward dynamic spin photonics and adaptive chiral optical components.

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• Chirality
• Electro-optic effects
• Metal-insulator transition
• Phase-change materials
• Polarization of light
• Heterostructures
• Metasurfaces
• Transition metal oxides