Seminars

Mott Memristors, Spiking Neuristors and Turing Complete Computing

Thursday, October 25, 2012

Dr. Stanley Williams

Abstract

Dr. Matthew Pickett and I have been collaborating on a project at HP Labs to explore the possibility of using "locally-active memristors" as the basis for extremely low-power transistorless computation. We first analyzed the thermally-induced first order phase transition from a Mott insulator to a highly conducting state. The current-voltage characteristic of a cross-point device that has a thin film of such a material sandwiched between two metal electrodes displays a current-controlled or 'S'-type negative differential. We derived analytical equations for the behavior these devices, and found that the resulting dynamical model was mathematically equivalent to the "memristive system" formulation of Leon Chua; we thus call these devices "Mott Memristors. We built Pearson-Anson oscillators based on a parallel circuit of one Mott memristor and one capacitor, and demonstrated subnanosecond and subpicoJoule switching time and energy. We then built a neuristor using two Mott memristors and two capacitors, which emulates the Hodgkin-Huxley model of the axon action potential of a neuron. Finally, through SPICE, we demonstrate that spiking neuristors are capable of Boolean logic and Turing complete computation by designing and simulating the one dimensional cellular nonlinear network based on 'Rule 137'.

Speaker Biography

R. Stanley Williams is an HP Senior Fellow at Hewlett-Packard Laboratories Director of the Cognitive Systems Laboratory. He received a B.A. degree in Chemical Physics in 1974 from Rice University and his Ph.D. in Physical Chemistry from U. C. Berkeley in 1978. He was a Member of Technical Staff at AT&T Bell Labs from 1978-80 and a faculty member (Assistant, Associate and Full Professor) of the Chemistry Department at UCLA from 1980 – 1995. He joined HP Labs in 1995 to found the Quantum Science Research group, which originally focused on fundamental research at the nanometer scale. He has over 130 US patents with ~100 pending and over 380 papers published in reviewed scientific journals. He was named to the inaugural Scientific American 50 Top Technology leaders in 2002 and then again in 2005 (the first to be so named twice). In 2005, Small Times magazine named the U.S. patent collection Williams has assembled at HP as the world’s top nanotechnology intellectual property portfolio.”