August 10, 2023

TCG CREST Colloquia

Topic: Robust Resistive and Mem-devices for Neuromorphic Circuits

Speaker : Prof. T. Venkatesan

                      Director: Center for Quantum Research and Technology University of Oklahoma, USA

Date: August 17, 2023

Time: 11:30 hr (IST)

Venue: TCG CREST, Bengal Eco Intelligent Park, 1st Floor, Block EM, Sector V, Salt Lake, Kolkata 700091
Online: Join LIVE TCG CREST channel of youtube

Artificial intelligence (AI) has been heralded as the flagbearer of the fourth industrial revolution but comes with a cost and that is computing power. It is projected that by 2040, we will need more computing energy than the total energy we can produce now. So, we need devices that can offer higher computing/ storage density with low energy consumption like neurons. We are addressing these challenges using oxide and molecular-electronic based memristors, which enable us to overcome the von Neuman bottleneck by co-locating the memory and computing functions on the same device, as in neuromorphic computing.

I will discuss a variety of strategies for forming oxide based memristors using different phenomena- band filling and creating a quasi-conduction band, using oxygen vacancies to create conductive percolation, using metal-insulator transitions, or using asymmetric tunneling at a ferroelectric barrier. The relative merits of the various approaches will be detailed.

In addition, I will touch upon memristive devices and circuits made from an azo-aromatic complex with extra-ordinary reproducibility, robustness, and scalability. These devices have been shown to switch with energies approaching atto-joules with measured switching times shorter than 5 ns. By using a simple cross bar array, we have shown that these devices perform with an energy-speed product 5000 times that of a state-of-the-art CMOS circuit.


1. Sreetosh Goswami*, Rajib Pramanick, Abhijeet Patra, Santi Prasad Rath, Ariando, Damien Thomson, T. Venkatesan*, Sreebrata Goswami* and R Stanley Williams*, Decision Trees within a Molecular Memristor, Nature, Sep. 3, 2021

2. Sreetosh Goswami, Adam J. Matula, Santi P. Rath, Svante Hedstrom, Surajit Saha Meenakshi Annamalai, Debabrata Sengupta, Abhijeet Patra, Siddhartha Ghosh, Hariom Jani, Soumya Sarkar, Mallikarjuna Rao Motapothula, Christian A. Nijhuis, Jens Martin, Sreebrata Goswami*, Victor S. Batista*, T. Venkatesan*, Robust resistive memory devices using solution-processable metal-coordinated azo-aromatics, Nature Materials, 16, 1216 (2017). News and views on this article: I. Valev and M. Kozicki, Non-volatile Memories: Organic Memristors come of age, Nature Materials, 16, 1170 (2017


T. Venkatesan- A Short Biography

Prof. T. Venkatesan is currently the Director of the Center for Quantum Research and Technology (Professor of Physics and ECE) at University of Oklahoma, and Scientific affiliate at NIST Gaithersburg. He is also the founding Director of the Center of Optimal Materials for emerging technologies (COMET) at OU. Prior to this he was Director of the Nano Institute at the National University of Singapore (NUSNNI) where he was a Professor of ECE, Physics, MSE and NGS. He wore various hats at Bell Labs and Bellcore before becoming a Professor at University of Maryland. As the inventor of the pulsed laser deposition (PLD) process, he has over 800 papers and 34 patents and is globally among the top one hundred

physicists (ranked at 66 in 2000) in terms of his citations (Over 51,186 with a hirsch Index of 115-Google Scholar). He has graduated over 56 PhDs, 35 Post Docs and over 35 undergraduates. He is also the founder and Chairman of Neocera, and Neocera Magma, companies specializing in PLD and magnetic field imaging systems and co-founder of Blue Wave Semiconductors. He recently helped launch two healthcare companies in Singapore, Cellivate and Breathonix. Close to 12 of the researchers (PhD students and Post Docs) under him have become entrepreneurs starting over 25 different commercial enterprises.

He is a Fellow of the Royal Society (FRS), National Academy of Inventors (USA), Singapore National Academy of Science, Asia-Pacific Artificial Intelligence Academy, American Physical Society (APS), Materials Research Society (MRS), winner of the Bellcore Award of excellence, George E. Pake Prize awarded by APS (2012), Distinguished Lectureship on the Applications of Physics Award- APS (2020), President’s gold medal of the Institute of Physics, Singapore, Guest Professor at Tsinghua University, Academician of the Asia Pacific Academy of Materials, Fellow of the World Innovation Foundation, past member of the Physics Policy Committee (Washington DC), the Board of Visitors at UMD and the Chairman, Forum of Industry and Applications of Physics at APS. He was awarded the outstanding alumnus award from two Indian Institute of Technologies- Kanpur (2015) and Kharagpur (2016), India.