Scientists at the Jawaharlal Nehru Centre for Advanced Scientific Research in Bengaluru, an autonomous institute of the Indian government's Department of Science and Technology, developed a new approach for fabricating an artificial synaptic network (ASN) that resembles the biological neural network using a simple self-forming technique (the device structure is formed by itself while heating).

The JNCASR team investigated a material system that mimicked neuronal bodies and axonal network connection, much like the biological system, in order to produce a synaptic device for neuromorphic applications with a simple fabrication procedure. They discovered that a self-forming mechanism was simple, scalable, and cost-effective for creating such a structure.

In their research, the JNCASR team dewetted Silver (Ag) metal to create branched islands and nanoparticles with nanogap separations that resembled bio neurons and neurotransmitters. Dewetting is a process that involves rupturing a continuous film into disconnected/isolated islands or spherical particles. Numerous higher-order cognitive activities can be simulated using such an architecture.

The fabricated artificial synaptic network (ASN) consisted of a Silver (Ag) agglomerates network separated by nanogaps filled with isolated nanoparticles. They discovered that dewetting the Ag film at a higher temperature culminated in the creation of island structures split by nanogaps, which resembled a bio-neural network.

This hierarchical structure simulated numerous learning activities such as short-term memory (STM), long-term memory (LTM), potentiation, depression, associative learning, interest-based learning, supervision, and so on, leveraging programmed electrical signals as a real-world stimulus. Excessive learning-induced synaptic exhaustion and subsequent self-recovery were also simulated.

According to the report, remarkably, all these behaviors were emulated in a single material system without the aid of external CMOS circuits. A prototyping kit has been developed to emulate Pavlov's dog behavior which demonstrates the potential of this device towards neuromorphic artificial intelligence. By organizing a nanomaterial resembling the biological neural substance, the JNCASR team has moved a step further in accomplishing advanced neuromorphic artificial intelligence.