Prem Piramanayagam of School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore

Abstract - Neuromorphic computing or brain-inspired computing is considered as a potential solution to overcome the energy
inefficiency of the von Neumann architecture for artificial intelligence applications [1-4]. To realize spin-based
neuromorphic computing practically, it is essential to design and fabricate electronic analogues of neurons and
synapses. An electronic analogue of a synaptic device should provide multiple resistance states. A neuron device
should receive multiple inputs and should provide a pulse output when the summation of the multiple inputs exceeds
a threshold.
Our group has been carrying out investigations on the design and development of various synaptic and neuron
devices in our laboratory. Domain wall (DW) devices based on magnetic tunnel junctions (MTJs), where the DW
can be moved by spin-orbit torque, are suitable candidates for the fabrication of synaptic and neuron devices [2].
Spin-orbit torque helps in achieving DW motion at low energies whereas the use of MTJs helps in translating DW
position information into resistance levels (or voltage pulses) [3]. This talk will summarize various designs of
synthetic neurons synaptic elements and materials [4]. The first half of the talk will be at an introductory level,
aimed at first-year graduate students. The second half will provide details of the latest research.
[1] K Roy, A Jaiswal and P Panda, Naure 575 607-617 (2019)
[2] WLW Mah, JP Chan, KR Ganesh, VB Naik, SN Piramanayagam, Leakage function in magnetic domain wall
based artificial neuron using stray field, Appl. Phys. Lett., 123 (9) 092401 (2023).
[3] D Kumar, HJ Chung, JP Chan, TL Jin, ST Lim, SSP Parkin, R Sbiaa and SN Piramanayagam, Ultralow Energy
Domain Wall Device for Spin-Based Neuromorphic Computing ACS Nano 17(7) 6261-6274 (2023)
[4] R Maddu, D Kumar, S Bhatti and S.N. Piramanayagam, Spintronic Heterostructures for Artificial Intelligence: A
Materials Perspective, Phys. Stat. Sol. RRL 17(6) 2200493 (2023).

Biography:

S. N. (Prem) Piramanayagam got the Ph.D. from the Indian Institute of Technology,
Bombay, India, in 1994. He carried out further research at Shinshu University, Japan
(1995–1999) and worked at the Data Storage Institute (DSI), Singapore (A*STAR). He
is currently an Associate Professor at Nanyang Technological University (NTU),
Singapore. He has 30 years of experience in magnetism, with research topics including
amorphous magnetic alloys, permanent magnetic materials, and thin films and
nanostructures for recording and spintronics applications. His current interest lies in the
interdisciplinary areas of magnetism, electronics, and nanotechnology.
Prem has received an award for teaching excellence from NTU Singapore and several
awards for outstanding research from DSI Singapore. He is a Senior Member of IEEE and has been an active
volunteer in the IEEE Magnetics Society, including chair of the Technical Committee, elected member of the
Administrative Committee, chair of the Singapore Chapter, and co-chair of the 2018 Intermag Conference in
Singapore. He has published over 200 journal articles and has filed several patent applications. He serves as an
editor of IEEE Transactions on Magnetics. He co-edited the book, Developments in Data Storage: Materials
Perspective (Wiley-IEEE Press, 2011).
Contact: prem@ntu.edu.sg

Address:Canada