IISc scientists develop brain-inspired analog computing platform capable of storing, processing data

Bengaluru: Researchers at the Indian Institute of Science (IISc) have developed a brain-inspired analog computing platform capable of storing and processing data in an astonishing 16,500 conductance states within a molecular film.

They believe it could be a game-changer, revolutionising industrial, consumer and strategic applications.

Published on September 11 in the journal Nature, this breakthrough represents a huge step forward over traditional digital computers in which data storage and processing are limited to just two states, the IISc said.

Such a platform could potentially bring complex AI tasks, like training Large Language Models (LLMs) to personal devices like laptops and smartphones.

These developments are currently restricted to resource-heavy data centres, due to a lack of energy-efficient hardware. With silicon electronics nearing saturation, designing brain-inspired accelerators that can work alongside silicon chips to deliver faster, more efficient AI is also becoming crucial.

"Neuromorphic computing has had its fair share of unsolved challenges for over a decade," explained Sreetosh Goswami, Assistant Professor at the Centre for Nano Science and Engineering (CeNSE), IISc, who led the research team. "With this discovery, we have almost nailed the perfect system – a rare feat," he said.

The molecular system at the heart of the platform was designed by Sreebrata Goswami, Visiting Professor at CeNSE. In a material film, molecules and ions create countless unique memory states, many of which have been inaccessible so far. Most digital devices can access only two states--high and low conductance, without being able to tap into the infinite number of intermediate states possible.

By using precisely timed voltage pulses, the IISc team found a way to effectively trace a much larger number of molecular movements, and map each of these to a distinct electrical signal, thus forming an extensive "molecular diary" of different states.

According to IISc, the fundamental operation underlying most AI algorithms is quite basic– matrix multiplication, a concept taught in high school maths. But in digital computers, these calculations hog a lot of energy. The platform developed by the IISc team drastically cuts down both the time and energy involved, making these calculations a lot faster and easier.

"This project brought together the precision of electrical engineering with the creativity of chemistry, letting us control molecular kinetics very precisely inside an electronic circuit powered by nanosecond voltage pulses," explained Goswami.

"Tapping into these tiny molecular changes allowed the team to create a highly precise and efficient neuromorphic accelerator, which can store and process data within the same location, similar to the human brain. Such accelerators can be seamlessly integrated with silicon circuits to boost their performance and energy efficiency," the IISc said.

Researchers said the key challenge was characterising the various conductance states, which proved impossible using existing equipment. The team designed a custom circuit board that could measure voltages as tiny as a millionth of a volt, to pinpoint these individual states with unprecedented accuracy.

It also turned this scientific discovery into a technological feat.

Using their AI accelerator, the team recreated NASA's iconic "Pillars of Creation" image from the James Webb Space Telescope data on a tabletop computer. This was achieved in a fraction of the time and energy required by traditional systems, IISc said.

The team includes several students and research fellows at IISc. They also collaborated with Stanley Williams, Professor at Texas A&M University and Damien Thompson, Professor at the University of Limerick, it added.

The researchers believe that this breakthrough could be one of India’s biggest leaps in AI hardware, putting the country on the map of global technology innovation. Navakanta Bhat, Professor at CeNSE and an expert in silicon electronics led the circuit and system design in this project.

"What stands out is how we have transformed complex physics and chemistry understanding into groundbreaking technology for AI hardware," Goswami said.

"In the context of the India Semiconductor Mission, this development could be a game-changer, revolutionising industrial, consumer and strategic applications. The national importance of such research cannot be overstated," he added.

With support from the Ministry of Electronics and Information Technology, the IISc team is now focused on developing a fully indigenous integrated neuromorphic chip. "This is a completely home-grown effort, from materials to circuits and systems," he emphasised.

"We are well on our way to translating this technology into a system-on-a-chip," he added.