Part-1 of the parent article mentions "The Dream Of Negative Capacitance". Unless you want to consider an inductor a negative capacitor, we still don't have Ne

Part-1 of the parent article mentions "The Dream Of Negative Capacitance". Unless you want to consider an inductor a negative capacitor, we still don't have Negative Capacitors. That Corp that makes studio grade audio processing ICs does have a "Non-Linear" capacitor that they use in several of their Design Notes: https://thatcorp.com/design-notes/ https://thatcorp.com/design-notes/ Negative Resistance, Capacitance, and Inductance can be synthetized with OpAmp Gyrator circuits. If you really want to go down into the weeds look up non-optical Parametric Amplifiers.