This paper demonstrates a new type of interconnects to fulfill the primary function of axons: transmitting electrical signals over long distances and at high speeds. The interconnect, which we call “ionic cable”, uses ions to transmit signals, and is built entirely with soft, elastic materials—elastomers and gels. The ionic cable is highly transparent, and remains functioning after being stretched nearly eight times its original length. We describe the design, theory and experiment of the ionic cable. We show that the diffusivity of signals in the ionic cable is about 16 orders of magnitude higher than the diffusivity of ions. We demonstrate that the ionic cable transmits signals up to 100 MHz over 10 cm, and transmits music signals over meters. The ionic cable transmits enough power to turn on light-emitting diodes. Our theory shows that the ionic cables scale well, suggesting tremendous opportunities to create miniaturized ionic circuit.
This paper was originally published in Extreme Mechanics Letters 3 (2015) Pages 59 - 65.
Click here to listen to an interview with author Prof. Zhigang Suo.
Researchers have unexpectedly discovered that ions conduct faster than electrons in conjugated polymers.