Goddard Space Flight Center, Greenbelt, Maryland 20771
ENGINEERING COLLOQUIUM
Monday, October 15, 2012 / 3:30 PM, Building 3 Auditorium
Stanley Williams
"Finding the Missing Memristor: Technology and Drama"
ABSTRACT -- In 2008, we published a paper in Nature entitled "The Missing Memristor Found". The title was intended to be a light-hearted pointer to a very important paper published in 1971 by Prof. Leon Chua of UC Berkeley that he entitled "Memristor – the missing circuit element," in which he predicted from only mathematical and symmetry considerations that there should be a fundamental new type of nonlinear circuit element to complement the resistor, capacitor and inductor that could remember its history by changing its resistance in response to the total flow of charge through the device.
This property, described by two deceptively simple equations now used as the definition for a memristor, is not only interesting from an academic point of view, but it is also very important technologically. Remembering resistance can be used for digital memory and storage applications. In fact, it appears to be possible to replace Flash memory, DRAM and magnetic hard disks with a single 'universal memory' technology that is nonvolatile, random access, and orders of magnitude faster than Flash. This possibility comes at an important time for the information technology community – it is getting more and more difficult to scale semiconductor devices down to obtain improved density, and it also turns out that the energy cost and time to move bits from DRAM to processor and even more from hard disks to DRAM are now the primary limiting factors in computing. A three-dimensional memristor-based cross-bar memory can in principle be stacked directly on top of a CMOS processor, an architecture that we term a 'nanoStore', which dramatically increases computational throughput while decreasing the power required for a particular computation. Memristors have also been proposed as critical elements in a wide variety of other applications, including Field-Programmable Gate Arrays and as synapses in a neuromorphic computing system.
The response to our 2008 paper has been astounding on several levels. First, the technical community has been fairly quick to recognize how the memristor model could be used in a wide variety of contexts, from electronic devices to explaining how amoeba learn. However, there has also been a significant response from the blogosphere and other venues – there is now a small but active group of "memristor deniers." There are bitter rivalries and there are examples of entities attempting to discredit the research and have patents invalidated. As difficult as it is, the science work is the easy part – the really hard part is predicting and understanding the human reactions and interactions related to it.
SPEAKER -- R. Stanley Williams is an HP Senior Fellow at Hewlett-Packard Laboratories, one of only five active technologists in HP with this title, and the 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. His primary scientific research during the past thirty years has been in the areas of solid-state chemistry and physics, and their applications to technology. In 2008, a team of researchers he led announced that they had built and demonstrated the first intentional memristor, the fourth fundamental electronic circuit element predicted by Prof. Leon Chua in 1971, complementing the capacitor, resistor and inductor. In 2010, he was named one of the first recipients of the HP CEO’s Award for Innovation for his work in sensing systems (CeNSE, the Central Nervous System for the Earth). He has received other awards for business, scientific and academic achievement, including the 2009 EETimes Innovator of the Year ACE Award, the 2007 Glenn T. Seaborg Medal for contributions to Chemistry, the 2004 Herman Bloch Medal for Industrial Research, and the 2000 Julius Springer Award for Applied Physics. He has over 130 US patents with ~100 pending, more than 200 patents outside the US, and over 380 papers published in reviewed scientific journals.