Spin as State Variable for Computation: Prospects and Perspectives

M_01_Kaushik Roy(Bio+Photo)
Kaushik Roy
Purdue University

Abstract :

Recent experiments on spin devices like magnetic tunnel junctions (MTJ’s), domain wall motion (DWM) in magnetic strips and spin valves have led to the possibility of having very high density on-chip memories and logic. While the possibility of having on-chip spin transfer torque memories is close to reality, several questions still exist regarding the energy benefits of spin as the state variable for logic computation. Lateral spin valves with multiple input magnets connected to an output magnet using metal channels or domain wall magnetic strips integrated with an MTJ, can be used to mimic the “perceptrons” or “neurons”. The spin-based neurons can be integrated with CMOS and other devices like domain wall magnetic strips to realize low-power all-spin neural networks (NN), and are suitable for big data analytics, such as data mining, image recognition, video analysis. Our analyses also show that DW based devices and MTJs mimic “spiking neurons” (having better bio fidelity than non-spiking neurons) with synaptic plasticity, leading to more energy efficiency and better self-learning capability. Finally, I will discuss possibilities of solving combinatorial optimization problems using the Ising computing model and the stochastic switching of spin devices.



Kaushik Roy received B.Tech. degree in electronics and electrical communications engineering from the Indian Institute of Technology, Kharagpur, India, and Ph.D. degree from the electrical and computer engineering department of the University of Illinois at Urbana-Champaign in 1990. He was with the Semiconductor Process and Design Center of Texas Instruments, Dallas, where he worked on FPGA architecture development and low-power circuit design. He joined the electrical and computer engineering faculty at Purdue University, West Lafayette, IN, in 1993, where he is currently Edward G. Tiedemann Jr. Distinguished Professor. His research interests include spintronics, device-circuit co-design for nano-scale Silicon and non-Silicon technologies, low-power electronics for portable computing and wireless communications, and new computing models enabled by emerging technologies. Dr. Roy has published more than 600 papers in refereed journals and conferences, holds 15 patents, supervised 70 PhD dissertations, and is co-author of two books on Low Power CMOS VLSI Design (John Wiley & McGraw Hill).


Award & Honors

  • 2015 Semiconductor Research Corporation Aristotle award
  • 2014-2019 DoD National Security Science and Engineering Faculty Fellow
  • 2013 IEEE Transactions on VLSI Best paper award
  • 2012 ACM/IEEE International Symposium on Low Power Electronics and Design best paper award
  • 2010 Humboldt Research Award
  • 2010  IEEE Circuits and Systems Society Technical Achievement Award
  • Distinguished Alumnus Award from Indian Institute of Technology (IIT)
  • Fulbright-Nehru Distinguished Chair
  • 2006  IEEE Transactions on VLSI Systems best paper award
  • 2006  IEEE/ACM International Symposium on Low Power Electronics & Design
  • 2005 SRC Technical Excellence Award
  • SRC Inventors Award, Purdue College of Engineering Research Excellence Award
  • 2005 IEEE Circuits and system society Outstanding Young Author Award (Chris Kim)
  • 2004 IEEE International Conference on Computer Design
  • 2003 IEEE Latin American Test Workshop
  • 2003 IEEE Nano
  • 2000 IEEE International Symposium on Quality of IC Design
  • 1997 best paper awards  International Test Conference
  • 1995 the National Science Foundation Career Development Award
  • IBM faculty partnership award
  • ATT/Lucent Foundation award


Professinal Activities

Dr. Roy was a Research Visionary Board Member of Motorola Labs (2002) and held the M.K. Gandhi Distinguished Visiting faculty at Indian Institute of Technology (Bombay). He has been in the editorial board of IEEE Design and Test, IEEE Transactions on Circuits and Systems, IEEE Transactions on VLSI Systems, and IEEE Transactions on Electron Devices. He was Guest Editor for Special Issue on Low-Power VLSI in the IEEE Design and Test (1994) and IEEE Transactions on VLSI Systems (June 2000), IEE Proceedings — Computers and Digital Techniques (July 2002), and IEEE Journal on Emerging and Selected Topics in Circuits and Systems (2011). Dr. Roy is a fellow of IEEE.