Bengaluru, Dec 2

Researchers at the Centre for Nano Science and Engineering (CeNSE), IISc, on Friday, have developed a highly energy-efficient computing platform that offers promise in building next-generation electronic devices.

The massive growth of data centres that consume enormous amounts of energy has contributed significantly to power shortages worldwide. According to IISc, there is a growing need to develop alternatives to conventional electrical components to make those systems more energy-efficient as the need for faster and more sophisticated computers and devices grows.

Memristors

Instead of using complementary metal-oxide semiconductors (CMOS), the team of scientists used components called memristors that can both store data and perform computation. Through this, they could cut down the number of components needed in a circuit, increase the speed and efficiency.

“We have now discovered a molecular circuit element that can capture complex logic functions within itself, facilitate in-memory computations in a smaller number of time steps, and use much fewer elements than usual,” said Sreetosh Goswami, Assistant Professor at CeNSE who led both the studies published in Advanced Materials. Existing computing architectures process and store data at separate physical locations. The back-and-forth communication between two locations consumes the lion’s share of the computing energy. “We are resolving this problem by performing both computation and storage at the same physical location,” he added.

The platform outperforms the current technologies by orders of magnitude, according to Goswami. “We are now able to make arrays of devices that are more robust, consistent and stable even compared to commercial technologies like flash memories,” he added.

Previously developed memristor-based circuits suffered from limitations in terms of speed and have a greater chance of errors accumulating because they carry out operations sequentially. However, the design of the new platform reduces the number of operational steps, increasing speed and reducing error, noted the researchers.

Higher efficiency

The metal-organic complexes used to build their platform were designed by Sreebrata Goswami, a Specialist Scientist at CeNSE. He said, “These complexes are like electron sponges that can take and give away electrons for billions of cycles without degradation. By making small chemical modifications – adding or swapping out one or two ions in the complexes, for example – researchers might be able to adapt the same circuit for multiple functions.”

The team states that for circuits that carry out mathematical operations compared with a typical CMOS circuit, the new platform offered 47 times higher energy efficiency and 93 times faster-operating speed, while only taking up 9 per cent of the physical footprint. 

The team plans to connect the platform to a sensor – for example, a smartphone screen that senses touch – and study how efficiently the platform processes the data it collects. Santi Prasad Rath, a postdoctoral fellow at CeNSE who designed and fabricated the circuit along with a PhD student, said, “In an Internet of Things (IoT) platform, this computing technology can be extremely useful.”  

“This necessitates the invention of new nanoscale device constructs to enable Moore’s Law over the next few decades,” explained Navakanta Bhat, Professor at CeNSE and an expert in CMOS technologies. “The fact that an emerging molecular platform is outperforming a mature technology is quite significant. This is high-stakes research that can help shape the future of our national mission in semiconductor electronics,” he added.