By Steve Bush 30th September 2022
Harvard scientists have managed to create a processing circuit usign ionics rather than electronics.
Working with biotech start-up DNA Script, they designed an ionic transistor which consists of an aqueous solution of quinone molecules, interfaced with two concentric ring electrodes with a centre disc electrode (see photo).
The ring electrodes electrochemically lower and tune the local pH around the centre disc by producing and trapping hydrogen ions.
A voltage applied to the centre disc causes an electrochemical reaction which generates an ionic current from the disk into the water.
The reaction rate can be sped up or down by tuning the local pH – increasing or decreasing the ionic current – allowing pH value to be used as a ‘gate’ to control current flow, and creating an ionic parallel to the electronic field effect transistor.
Hundreds of pH-gated ionic transistors were built on the same substrate, arranged so that disk current would be an analogue arithmetic multiplication of the disk voltage and the local pH value.
A 16 x 16 array of similar ionic transistors became an analogue matrix multiplyer, with all the different local pHs storing a weight matrix for the equation.
“Our ionic circuit performs the matrix multiplication in water in an analogue manner that is based fully on electrochemical machinery,” said Harvard researcher Woo-Bin Jung. “Matrix multiplication is the most prevalent calculation in neural networks for artificial intelligence.”
“So far,” continued Jung, “we have used only three or four ionic species, such as hydrogen and quinone ions, to enable the gating and ionic transport in the aqueous ionic transistor. It will be very interesting to employ more diverse ionic species and to see how we can exploit them to make rich the contents of information to be processed.”
The research is published in Advanced Materials.
Tagged with: Harvard neural network
Your email address will not be published. Required fields are marked *
Download the Elektra Awards 2022 media pack and book your sponsorship package to be part of the most prestigious awards event celebrating its 20th anniversary this year!
Have your say in choosing the most promising UK university research project reported in the last year, from Bristol or ICL to Surrey or Southampton, and robotic fingers to flexible and stretchy supercapacitors...
Get our news, blogs and comments straight to your inbox! Sign up for the Electronics Weekly newsletters: Mannerisms, Gadget Master and the Daily and Weekly roundups.
Read our special supplement celebrating 60 years of Electronics Weekly and looking ahead to the future of the industry.
Read the Electronics Weekly @ 60 supplement »
Read the first ever Electronics Weekly online: 7th September 1960. We've scanned the very first edition so you can enjoy it.
Read the very first edition »
Electronics Weekly teams up with RS Grass Roots to highlight the brightest young electronic engineers in the UK today.
Read our special supplement celebrating 60 years of Electronics Weekly and looking ahead to the future of the industry.
Read the Electronics Weekly @ 60 supplement »
Read the first ever Electronics Weekly online: 7th September 1960. We've scanned the very first edition so you can enjoy it.
Read the very first edition »
Tune into this Xilinx interview: Responding to platform-based embedded design
Tune into this podcast to hear from Chetan Khona (Director Industrial, Vision, Healthcare & Sciences at Xilinx) about how Xilinx and the semiconductor industry is responding to customer demands.
By using this website you are consenting to the use of cookies. Electronics Weekly is owned by Metropolis International Group Limited, a member of the Metropolis Group; you can view our privacy and cookies policy here.