Abstract: A method of generating a negative capacitance in a capacitor device is provided. The method comprises providing the capacitor device. The capacitor device comprises an active layer of vanadium dioxide (VO2) and two electrodes connected thereto. The active layer is excitable between its semiconducting state and its metallic state. The method comprises exciting the active layer with an excitation source, thereby bringing the active layer from the semiconducting state to the metallic state and generating the negative capacitance between the two electrodes. Systems for generating a negative capacitance are also provided.