Negative capacitor takes power only where it is needed

This image shows the motion of the domain wall (ac and bd) in a capacitor when a charge is added to one side (c). The resulting redistribution of the domain wall causes a negative capacitive effect

Negative capacitor

After exploring the negative capacitance to create a transistor that spends less energy, researchers are now exploring the strange phenomenon to create new ways of storing and redistributing energy on the scale of microchips.

Igor Lukyanchuk and his colleagues from the USA, France, and Russia created a static and permanent negative capacitor, a component that up to 10 years ago was seen as a violation of the laws of physics.

While the previously proposed projects for negative capacitors operated on a temporary and transient basis, the new concept functions as a steady-state reversible device.

In traditional capacitors, the component's electrical voltage is proportional to its stored electrical charge - increasing the amount of stored charge increases the voltage. In negative capacitors, the opposite happens - increasing the amount of charge decreases the voltage.

Since the negative capacitor is a part of a larger circuit, this does not violate the law of energy conservation.

Electricity on demand

The team found that by pairing a negative capacitor in series with a standard positive capacitor, it is possible to locally increase the voltage on the positive capacitor to a point higher than the total system voltage.

In this way, it becomes possible to distribute electricity to regions of a circuit that require more voltage, while the bulk of the circuit remains running at low voltage.

This allows to rationalize the use of electricity inside chips and electronic circuits, using only what is strictly necessary, while still meeting the variable demands of each part of the circuit.

With this, it becomes possible to build circuits that consume less energy - the battery lasts longer - and heat less.

Bibliography:  Harnessing ferroelectric domains for negative capacitance I. Lukyanchuk, Y. Tikhonov, A. Sené, A. Razumnaya, VM Vinokur  Nature Communications Physics Vol .: 2, Article number: 22 DOI: 10.1038 / s42005-019-0121-0