Dielectric elastomers improve and simplify rubbery electronics

Dielectric elastomers are electroactive polymers, a soft material that reacts to an applied electric field. They are used in soft robotics for moveable and wearable structures, can act as sensors to monitor quantities like pressure, and are promising materials for energy harvesting.

While the elastomers have a good response time, amount of actuation, and ratio of mass-to-energy, tapping into their full potential requires compatible electronics.

By implementing the design techniques adopted in conventional electronics, Ciarella et al. constructed digital circuits from dielectric elastomers. These rubbery circuits use elastomers in a similar way to transistors in traditional electronics.

The group showed alternative ways to design NOR and XOR gates in rubbery electronics. Using more sophisticated techniques, they created a multiplexer.

“Multiplexers are a quite important building block in electronics,” said author Luca Ciarella. “Without using this technique, it would have been quite complicated and required a lot of logic gates.”

Conventional 2-channel multiplexers are built using seven transistors and four resistors. However, only two dielectric elastomers are required with the author’s pass transistor logic technique, which reduces power consumption by avoiding direct connections between the supply and ground.

In the future, the team aims to improve their circuits and delay times, as well as build more advanced rubbery circuits.

“Dielectric elastomers are an active material with a lot of functions that, in general, materials do not have. They are unique in their multifunctionality,” said Ciarella.

Source: “Digital electronics using dielectric elastomer structures as transistors,” by Luca Ciarella, Andreas Richter, and Ernst-Friedrich Markus Henke, Applied Physics Letters (2021). The article can be accessed at https://doi.org/10.1063/5.0074821 .