Tech Talk iconTech Talk

The men behind memristance



The memristor is all over the news today. The fourth circuit element discovered at last!

I can't overstate what a big deal this is. My editor forwarded me the press release with a note asking if I thought it was a really late April Fool's joke.

Usually our reporting takes the form of "smallest chip created!" or "farthest constellation photographed!" or "most powerful microscope invented!" -- That's about as enthusiastic as things get in this corner of the journalism world. (Not that there's anything wrong with smaller transistors.) But let's face it, it's the same headline this year, next year, and the year after that. But how often do we get to write about something completely new?

I was excited: but Stan Williams, the HP scientist who discovered the new element, was practically jumping up and down when I talked to him. "It was pretty euphoric," he told me. (I don't hear that word a lot.)

This ended up being a genuine mystery story, complete with hidden treasures and forgotten maps (that map being the 1971 paper by Leon Chua that foretold the existence of a fourth circuit element). Williams said the memristor has been sitting there waiting for someone to discover it for over 100 years. "There was no reason for people even during Maxwell's time not to have come up with a memristor," he said. "It took Leon to figure out that there was something that should be there. And then it took another 40 years until I was able to figure out what it was and how to make it."

Chua was excited too (and by the way, Chua is a big, big deal in the engineering community). He told me electronics engineering text books will need a rewrite. "I'm very happy," he told me. "This is a breakthrough that will set a paradigm shift!"

Chua was so excited that he kept mixing his metaphors-- every time he talked about the memristance phenomena that people had been seeing in their nanoscale devices, he would tell me that the nano community had been "barking up the wrong horse."

I will say one thing, though: memristor? Really? It took me three days to stop saying memresistor, a full week to stop typing memresistor, and all the while my editor kept changing memristor to memresistor in the story.

It's still early in the game-- it's not in the textbooks yet! Is there still time to change the name?

Purdue supercomputer to be installed in just one day

Purdue plans to assemble what will be the world's 40th ranked supercomputer in just one day, 5 May to be exact.

I worry, not that they won't make their deadline, but that, in the rush, one of the 200 volunteer assemblers will become inextricably entangled in the interconnects in such a way that for Purdue to meet its deadline, he or she will have to spend eternity (or at least the night) inside the supercomputer.

Don't laugh. It happened to Mike Mulligan and his steam shovel. Except Mike was trying to dig the cellar of Popperville's new town hall in just one day, not assemble a supercomputer. If you're not familiar with the story, Mike and Maryanne (the steam shovel) won't get paid unless he digs the cellar in one day, a feat that would take 100 men a week to do. They dig it in such a rush, they forget to leave a way out for Maryanne. The solution is to make Maryanne the town hall's furnace and Mike the town hall's janitor. So they just build the town hall right over the pair of them. Mike gets an easy job and Maryanne keeps puffing steam. All's well.

Maybe the interconnect-entangled student could get a tech-support gig.

From the press release:

May 1, 2008

Purdue to install Big Tenâ''s biggest campus computer in just a day

WEST LAFAYETTE, Ind. - The largest supercomputer on a Big Ten campus will be installed at Purdue in a single-day, electronic "barn-raising.â''

More than 200 employees will gather May 5 to help build the massive machine, which will be about the size of a semitrailer when installed. It will be the largest Big Ten supercomputer that is not part of a national center.

Purdueâ''s computer is being built in a single day to keep the university's science and engineering researchers from facing a lengthy downtime, says Gerry McCartney, vice president for information technology and chief information officer.

"Our staff thought we were insane when we challenged them to build such a big computer in a single day," McCartney says. "But now thereâ''s real excitement to be a part of this."

To generate interest on campus, the organizers created a spoof movie trailer called â''Installation Day,â'' which is a take off of the movie â''Independence Day.â'' The video can be seen on YouTube at

Supercomputers are ranked by their performance in running a complex benchmarking system. The results of the tests are published twice each year at Purdueâ''s new supercomputer would rank in the top 40 of the current Top 500 list, which was published in Nov. 2007.

Will NIST's Proto-Prototype Nano Assembler Lead to Prototypical Mechanosynthesis?

Recent research at the National Institute of Standards and Technology (NIST) using MEMS devices to move atoms instead of employing atomic force microscopes (AFMs) as mentioned in the article has opened up the possibility for a new tool in nanomanipulation. Radical nanotechnology proponents are heralding it as an enabling technology for molecular manufacturing.

One of the knocks on STM and AFM nanomanipulation, at least in terms of it being â''protypical mechanosynthesisâ'', is that the manipulation does not involve â''reactive (and re-chargeable) molecular toolsâ''.

Jason Gorman of the Intelligent Systems Division at NIST, who will publish the research in a forthcoming issue of the International Journal of Nanomanufacturing, has taken a different approach to the typical use of AFMs for nanomanipulation and the result could pass the "reactive and rechargeable molecular tool" test.

Gorman and his colleagues at NIST have developed a system that is described in the article announcing the research as â''four MEMS devices positioned around a centrally located port on a chip into which the starting materials can be placed. Each nanomanipulator is composed of a positioning mechanism with an attached nanoprobe. By simultaneously controlling the position of each of these nanoprobes, the team can use them to cooperatively assemble a complex structure on a very small scale.â''

Whether or not the MEMs-device system fits into a definition of mechanosynthesis or not, it appears that the technology could overcome some of the difficulties faced with top-down nanomanipulation using AFMs, such as nanoparticles sticking together during manipulation making them impossible to be lifted from the substrate.

The result could be nanoassembly systems that could be made for around $400 per chip, making them thousands of times cheaper than macro-scale systems such as the AFM.

Trust in Integrated Circuits

DARPA's Trust in Integrated Circuits program has been hitting the news on and off over the past few months, ever since they released the details of the program back in December. The program, which aims to verify the integrity of the electronics that will underpin critical military hardware like the F-35 Joint Strike Fighter, could give the military, and defense contractors, a guaranteed way to check if their chips have been compromised.

If the program pans out and produces a real way to verify microprocessors, itâ''ll be interesting to see how a Trusted chip imprimatur will play with the Trusted Foundries program. (Trusted Foundries were set up to counter what the DoD perceives as a rising threat to defense microelectronics posed by the offshoring bleed in the semiconductor industry.) Every article about the DARPA program (including mine) maintains that there is no conflict between a chip verification method and the Trusted Foundries program.

Will a DARPA Good housekeeping seal of approval become a standard last step in the trusted foundry procedure? Will one of these Trusted Entities get knocked out of the ring, or will the government integrate them into one oversight body?

All of this brings me to the point: On April 9, Northrop Grumman announced that its Advanced Technology Laboratories (ATL) semiconductor plant, in Maryland, had just achieved Trusted Foundry status. In fact, their accreditation is Category 1A which is, as you'd expect, the highest level that can be awarded to a foundry. A scant two weeks later, they won multiple contracts for the F-22 Raptor. Northrop gets $252 million to design and manufacture the F-22â''s communications, navigation and identification subsystems. Thatâ''s a lot of chips.

The programs themselves are not in conflict. The first question might be: if you have a way to â''ensureâ'' that a chip is pure, why do you need your own (more expensive) stateside fabs? Because you don't want someone reverse engineering your most mission critical circuits, like the stuff that goes into an F-35. Thatâ''s a no-brainer.

But there are an awful lot of cooks working on the soup.

Trusted Foundries by definition are onshore, and they go through an accreditation process that can only be called grueling; verifying a facility can take months to years.

Then you have your Trusted Designers, like Sandia National Laboratoriesâ'' microelectronics center. These guys design the chips, but their Paleolithic .35 micron fab is ill-equipped to produce chips for anything anyone needs these days, so they send the designs to a trusted foundry to produce.

But some people don't even agree that they're safe once they've hit the foundry. "Even domestically there may be problems," HRLâ''s Charles Henry Field told me (HRL is one of the official TAPO trusted foundries). You need trust all the way through the supply chain. Malicious tampering could happen all the way down the chainâ''what about the delivery truck?"

So what exactly will IARPA do?

When I interviewed Lisa Porter about the kinds of projects the Intelligence Advanced Research Projects Activity (the web site isn't quite ready for prime time, but should be up within a week) would take on, she would not get specific, because most of those projects will be classified. But Carl Landwehr, a program leader at the National Security Agency, elaborated on what projects are now being considered at IARPA. These include revamping the infrastructure of the internet to counter threats like the Storm worm, and addressing fundamental software flaws that prevent true cybersecurity.

Cybersecurity is becoming a major concern, and doubly so for the intelligence community. For intelligence analysts, assurance that their information is solidly based and not sabotaged in any way is extremely important. Some IARPA projects will focus on techniques that will stop the multitudes of attacks on the flaws built into commercial software. Itâ''s no secret that that commercial software often ends up in military (and other classified) environments. Security is not the primary consideration during the cycle of that softwareâ''s design: it certainly does not take precedence over time to market and features. â''The flaws in software implementations are often exploited by attackers,â'' Landwehr says. That doesnâ''t mean exploitation is easy, but one of IARPAâ''s priorities, he says, will likely be to look into techniques to thwart these attacks.

Landwehr also points to Storm as a consequence of an existing infrastructure that provides weak accountability. "There's a lot of bleeding out there," he says. "Network attacks have become a commercially productive activity for a lot of people who are trying to make money. That's an urgent concern. With the current infrastructure, itâ''s very difficult to trace back attacks, or even to tell when youâ''re being attacked. Packet streams can come at you from anywhere.â'' IARPA is interested in funding long-term research that would make it more difficult for a Storm type of threat to occur. "We could spend a lot of research money on trying deal with current attacks and never really solve the problem," he says. "But if we spend some effort looking further out, we might change the infrastructure so that these attacks just couldnâ''t happen."

High Gasoline Prices Start to Bite into Driving, SUV Ownership

With U.S. gasoline prices at an all-time high, having climbed in fits and starts for five years, the logical results appear to be finally showing up in lower gasoline consumption and a distaste for large cars and light trucks. According to a report in the May 5 issue of Business Week, the number of vehicles on the roads dropped 1.4 percent last year, and gasoline consumption is expected to dip 0.7 percent this year. Sales of SUVs and pickup trucks plummeted 27 percent in the first quarter of 2008, with total auto sales down 8 percent.

Will oil and gasoline prices continue to trend upward and stay there, or is the current situation just a blip? That is the question. If high prices are here to stay, then of course those who immediately replace their big cars with smaller ones will come out ahead of the game, and those automakers who anticipate that behavior will be the winners. Ford Motor, which reported a surprisingly large first-quarter profit last week, is among those betting that high prices are here to stay, says Business Week.

Ironically, if gasoline prices stay in the stratosphere, the United States may be off the hook when it comes to the atmosphere. Back-of-the-envelope calculations suggest that if one wanted to halve carbon emissions from the U.S. automotive sectorâ''enough to get the country into step with international efforts to reduce greenhouse gasesâ''gasoline prices would have to double from their average levels of the past few years, which have been around $2.50. That calculus underlay a blue-ribbon report sponsored by Princetonâ''s Woodrow Wilson School last year, which recommended increasing gasoline prices by $2.50 per gallon over a period of 10 years--in effect doubling the gasoline price as a matter of policy.

Of course that's a far cry from any policy being discussed out on the campaign trails. McCain, joined by Clinton, has proposed suspending the Federal gasoline tax of 18.4 cents for the summer months, to help out drivers and give the economy a little boost. Obama has dismissed the idea as ineffectual.

If however market forces were allowed to drive the gasoline price to $5, and American consumers started to believe it was really going to stay that high, thenâ''arguably!â''policy wouldnâ''t be necessary. Over time, if econometric studies are to be believed, American drivers would spontaneously use half as much gasoline and emit half as much carbon.

Thereâ¿¿s New Climate Science Under the Sun

To hear some climate skeptics say it, youâ''d think the greenhouse effect was just a theory, concocted by dangerous radicals to undermine the American way of life; and to hear some of the climate alarmists, youâ''d think 100 percent of the science was nailed down, with nothing new to learn and nothing left to argue about. Well, a report by French and Russian scientists in Physical Review Letters, the worldâ''s premier publisher of new physics discoveries, finds that the mechanisms responsible for trapping the Sunâ''s radiation in the Earthâ''s atmosphere have been imperfectly understood. (Journalists can obtain pre-publication copies of the article at the American Institute of Physicsâ'' physics news/select.)

As every basic textbook in atmospheric science will tell you on page 1, the greenhouse effect is something of a misnomer: in an actual greenhouse, warming occurs because the glass roof stops the convection currents that normally carry warmer air up and away; in Earthâ''s atmosphere, warming occurs because the infrared radiation reflected back from the Earthâ''s surface is trapped by the greenhouse gases in the atmosphereâ''natural water vapor is by far the most important among them but human-generated carbon dioxide is increasingly significant.

Michael Chrysos and colleagues at the University of Angers and collaborators at the University of Saint Petersburg confirmed that absorption of IR radiation by triatomic carbon dioxide molecules is governed by the laws of quantum physics, involving their internal vibrations. But they found that IR absorption also occurs in collisions between CO2 moleculesâ''and in collisions of diatomic molecules such as O2 and N2 as wellâ''and that this kind of absorption is explained by Newtonian mechanics.

The Chrysos team estimates that the collisional IR absorption accounts for about 10 percent of the total greenhouse effect on Earth. On Venus, which has a super-hothouse climate, they believe the collisional absorption explained by classical mechanics may account for more than half the effect.

Navy Retreats From Astronaut Program After 50 Years

In a sign of cautiousness in uncertain times, the U.S. Navy has ordered most of its officers to refrain from volunteering for the nation's astronaut training program.

According to a report in The New York Times, the Navy has advised its astronaut corps applicants from several specialties that they will no longer be considered for nomination to the elite space-flight school.

The move comes, ironically, as the U.S. celebrates the 50th anniversary of the National Aeronautics and Space Administration (NASA).

It also marks a retreat from an historic embrace of the American space exploration program that began with the Navy's participation in the Mercury Seven project, begun 49 years ago, in which three of the first astronauts, Scott Carpenter, Wally Schirra, and Alan Shepard, were naval officers.

Shepard was America's first astronaut to fly into space, in 1961.

In the Times article, Navy officials said the reason for the new restriction lies in a desire by the service to ensure that its mission critical officers are retained in traditional combat roles during time of war.

Vice Admiral J. C. Harvey Jr. last month wrote a memo saying that applications for Navy nominations to the space program from 10 specialties would not be accepted "due to critical inventory shortfalls and/or priority global war on terrorism skill set requirements," according to the Times. The specialties specifically mentioned include special forces, combat engineers, and academics, among others. Navy aviators, however, are not among the specialties affected.

Over the past 15 years, the Navy has nominated as many as 211 and as few as 105 candidates per year for consideration by NASA, though groups from earlier years numbered as low as 34. This year, the service allowed 5 applications to be submitted originally, but that number was expanded to 50 after reconsideration by Adm. Wright.

William M. Shepherd (Capt. USN-Ret.), who served as the first commander aboard the International Space Station, told the Times he was concerned whether the decision marked a shift in America's attitude toward space travel.

"This is the first tick of the needle," he noted. "Our commitment to doing this might be changing. This is important beyond the Navy, beyond NASA."

Officials from the Air Force, Army and Marine Corps told the Times their services were not restricting astronaut training applications.

It may be only a small course correction by the Navy (for the best of reasons), but it definitely has the outward appearance of a sea change for a military branch that has long taken pride in the helmsmanship of its officers voyaging to the ocean of space.

Out of Africa: IBM sees opportunity

IBM is getting serious about sub-Saharan Africa -- both as a consumer and producer of high-end computing.

For the past year, Mark Dean, an IBM Fellow and vice president of the company's venerable Almaden Research Center in San Jose, has traveled widely across the region, looking for new opportunities for the computer company. In the process, Dean brokered a donation of an IBM supercomputer to the Center for High Performance Computing in Cape Town and helped to launch a mentoring program that pairs IBM researchers with African university students.

Dean, who will give a public talk on new African opportunities in information technology on May 8 at Almaden, is helping to give sub-Saharan Africa a higher profile at IBM. In a recent op-ed in the San Jose Mercury News, he said that the cell phone is emerging as the central information device in the region.

In an interview, Dean told me he hopes IBM will double its number of employees in sub-Saharan Africa over the next three to five years. Today, the company employs about 2,000 people, mostly in South Africa, a traditional stronghold for IBM. Dean says gets about $2 billion in revenue from the region, with about half coming from South Africa.

IBM isn't only selling into Africa. Dean envisions African engineers and codewriters creating a new-generation of cell phone applications. While Dean thinks Africans need to raise their skill levels, IBM isn't waiting to give talented Africans a chance at creating products. The company recently opened a "software solutions lab" in South Africa to create products. IBM also wants to sell more back-end computer systems to support digital services offered over cell phones.

"We're taking baby steps," Dean says. But he's convinced that "IBM should invest more and develop our brand" in the region.

Smog Blog: Mega Mexico City in Tough Pollution Fight

Vacationing here in Mexicoâ''s Federal District, one of the worldâ''s biggest of megacities, you canâ''t ignore the bad air. Last year, in IEEE Spectrum magazineâ''s special issue about megacities, Erico Guizzo drew attention to the innovative way Sao Paulo has introduced special reserved bus lanes to make bus travel speedier and discourage private cars. In Mexico Cityâ''s Insurgentes, the main thoroughfare that traverses the city much as Broadway cuts diagonally all the way up Manhattan, lanes reserved for express buses also are to found.

Those dedicated bus lanes are just one of the many ways that Mexico City keeps a lid on inner-city traffic and automotive emissionsâ''this splendid city has an outstanding subway system that the French and which costs just 20 pesos to ride (two U.S. cents) and ubiquitous minibuses (including the lovely new Volksbus built by VW). But in a sprawling metropolitan area of close to 20 million people, at a high altitude where the air is thin to begin with and catalytic converters work poorly, and where so many antiquated cars and trucks belch putrid fumes, curtailing air pollution is an uphill battle.

Five years ago, before Guizzo graced IEEE Spectrum with his presence, he wrote an article for a competitor publication (that we naturally prefer not to name) about how Luisa T. Molina and her husband the Nobelist Mario Molina had organized a program at MIT and Harvard to study air pollution in major urban areas worldwide; they have done closely related work in a joint program in La Jolla. Erico described how the Molinas had vans equipped with state-of-art monitors drive around Mexico City to test air and identify mobile and point sources of pollution.

That article came vividly to mind two days ago as I drove back into the city with my wife and son from Teotihuacan, the spectacular 2000-year-old complex of pyramids and temples northwest of the Federal District. We had the bad luck to get caught in a highway bottleneck, where a superhighway was being extended. For close to an hour and a halfâ''resulting finally in a little burst of road rage on my part, a minor moving violation, the threat of a ticket, and the usual bribe paid to a well-organized group of extortionist traffic copsâ''we sat nearly motionless behind decades-old trucks belching black diesel smoke.

With some feeling of chagrin we thought and talked about how when the superhighway was completed, there would be fewer trucks sitting motionless spewing pollutantsâ''but there also would be all the more trucks and cars speeding along the new highway into and out of the city.

That night we were blessed with a gigantic thunderstorm, and when we woke the next morning, the sky over Mexicoâ''s downtown was miraculously clear blue. I took my son up to the top of the television tower, to catch a rare glimpse of the two sacred volcanoes that loom over the city, almost always invisibly.

Astonishingly and yet not so astonishingly, when we got to the top of the tower, everything right under us in the inner city was beautifully clear. But all around there was a doughnut of pollution so dense, we not could see through or over it to Popocatepetl and Ixtaccihuatl (Popo and Ixta). In the inner city with its fabulous subway system, adorable VW minibuses, and dedicated express bus lanes, the air was almost pristine. But all around, where the city is sprawling cancerously in every direction, the air was perhaps worse than ever.


Tech Talk

IEEE Spectrum’s general technology blog, featuring news, analysis, and opinions about engineering, consumer electronics, and technology and society, from the editorial staff and freelance contributors.

Newsletter Sign Up

Sign up for the Tech Alert newsletter and receive ground-breaking technology and science news from IEEE Spectrum every Thursday.

Load More