Research

Hardware-efficient learning systems, neuromorphic AI, in-memory computing, and the physics of low-precision devices.

Academic Journey

Jan 2016 – Feb 2019

PhD — New Jersey Institute of Technology

Doctoral research in the Department of Electrical and Computer Engineering. Focused on high-performance learning systems using low-precision nanoscale non-volatile memory devices, with direct applications in energy-efficient hardware implementations of deep neural networks.

Neuromorphic Computing Phase-Change Memory Deep Learning Hardware RRAM
Outstanding Graduate Student Award & Hashimoto Prize for Doctoral Candidate — 2019

April 2019 – March 2021

Postdoctoral Researcher — IBM Research Zürich

Joined the In-Memory Computing group at IBM Research Zürich. Investigated hardware-aware training techniques for analog AI accelerators, characterised precision limits of Phase-Change Memory (PCM) devices, and contributed to foundational work on in-memory computing for homomorphic encryption.

PCM Devices Hardware-Aware Training In-Memory Computing Homomorphic Encryption Patent

📄 Patent granted: In-memory computing architecture for homomorphic encryption

Outstanding Technical Achievement Award – Analog AI Chip Cloud Demo — 2019

2021 – Present

Independent Research & Exploration — Zürich

Pursuing independent research bridging neuromorphic computing, consciousness theory, and contemplative science. Developing a unified hypothesis connecting perception, measurement, and universal intelligence.

Consciousness Theory Contemplative Science Open to Collaboration

High-Performance Learning Systems Using
Low-Precision Nanoscale Devices

New Jersey Institute of Technology · January 2016 – February 2019

Thesis Overview

Computers were an imitation of human brain from the very beginning. Though we were aware of the neural architecture of the brain, technology at the time favored the von-Neumann architecture. While the memory and processing are at the same physical location in a biological neural network, they are separate in the von-Neumann architecture. This meant constant data shuffling and were a major source of energy inefficiency. Supercomputers consuming millions of Watts still could not perform tasks that human brain can with mere 20 Watts.

Simply adopting the neural architecture was not sufficient. The energy efficiency problem demanded, we also address how we implement them on the physical hardware. This is where Neuromorphic engineering and In-Memory Computing came in. Both of these approaches attempts to process signals uing the physical characteristics of arrays of memory devices.

In this thesis, we brings to light the key challenges faced in this field, and directly addresses the precision limits of these memory device by experimental demonstration of several architecture modifications to maintain high accuracy.


Publications

Full list on Google Scholar ↗

Nano Letters · 2016

A 250 mV Cu/SiO2/W Memristor with Half-Integer Quantum Conductance States

N. S. Rajalekshmi et al. · PDF ↗

IEEE nanotechnology magazine · 2018

Building Brain-Inspired Computing Systems - Examining the role of nanoscale devices

N. S. Rajalekshmi et al. · PDF ↗

Frontiers in Neuroscience · 2020

Mixed-Precision Deep Learning Based on Computational Memory

N. S. Rajalekshmi et al. · PDF ↗

Scientific Reports · 2020

Supervised learning in SNNs with PCM synapses

N. S. Rajalekshmi et al. · · PDF ↗

Patent · 2022

In-Memory Computing Architecture for Homomorphic Encryption

IBM Research Zürich — US11907380B2

+ More publications on Google Scholar

News & Awards

Research Grant

Grant Award Coverage

IBM PhD fellowship awarded for work in neuromorphic computing and AI hardware.

Read News Coverage ↗

Award

Hashimoto Prize for Doctoral Candidate

Recognised with Outstanding Graduate Student Award and Hashimoto Prize for Doctoral Candidate in ECE, NJIT