This is a great idea! Things are changing so rapidly, one must continuously seek out the technological changes that could completely wipe your business model.
http://www.businessweek.com/print/magazine/content/09_12/b4124044178284.htm
Rise of the Machine
March 12, 2009, 5:00PM EST
Singularity U.: It's No Sci-Fi Fantasy
The new university, named after a futuristic vision, is drawing a lot of serious attention
By Ellen Gibson
Bill Gates calls him "the best person I know at predicting the future of artificial intelligence." Computer scientist Douglas Hofstadter classifies his ideas as "the craziest sort of dog excrement."
Ray Kurzweil is no stranger to controversy. For more than a decade, the inventor-turned-author has been issuing predictions about superhuman cyborgs and biotech-based immortality that border on science fiction. Yet Kurzweil's theories continue to gain traction among mainstream techies, and they are also making their presence felt in corporate boardrooms. The latest vindication: Google (GOOG) and NASA are backing a new university modeled on his ideas, with additional funding from X Prize creator Peter H. Diamandis.
Dubbed "Singularity University" and housed at NASA Ames Research Center in Mountain View, Calif., the institute will feature intense 3- and 10-day workshops to help senior executives steer their companies into the future. Announced at the Technology, Entertainment, Design (TED) conference in February, the school has recruited top-tier faculty, including Vint Cerf, Google's chief internet evangelist, and Jim Karkanias, a research director at Microsoft. And among the students inquiring about the first executive classes this fall are venture capitalist Heidi Roizen and Judy Estrin, former chief technology officer of Cisco (CSCO) Systems.
Some of the topics discussed in class would feel right at home at a Star Trek convention. Take the name of the new institute. In astrophysics, "singularity" refers to conditions on the far side of a black hole. But it was Kurzweil who gave the term new resonance in his 2005 best seller, The Singularity Is Near. Here, it designates a point in the not-so-distant future when artificial intelligence will outstrip human brainpower and ingenuity. (Think IBM's Deep Blue vs. Kasparov, on a planet-wide scale.) In Kurzweil's best-case scenario, man will merge with machines via tiny robotic devices implanted in our bodies and brains, extending our lifespans and vastly enhancing our mental prowess. Bionic brains, Kurzweil says, will make short work of the world's intractable problems, from climate change to drug-resistant diseases.
The school's mission isn't to indoctrinate students with Kurzweil's futurology—or even grant degrees. Instead, it's to help them grasp the implications of fast-changing fields such as biotechnology and robotics. Graduate and postgrad students will have nine weeks to absorb these lessons, while accelerated classes for C-suite teams will provide an overview of how disruptive technologies trample existing industries and forge new ones. Executives will be placed in small groups for focused peer-to-peer engagement. For example, the CEO of a company that makes silicon-based solar cells will be in a group that explores the impact of exotic new materials. Managing intellectual property, of course, is part of the core curriculum.
"We're going to be focusing very much on the science, not the science fiction," says Salim Ismail, the university's executive director and former product development chief at Yahoo! (YHOO) Five years ago, people might have been shocked to hear that ink-jet printing could be used to assemble living cells into artificial organs. "Today they're close to getting prototypes working in labs," he says. "What will we see in the next five years?"
FAST AND FAR-REACHING
Borrowing from microelectronics, Kurzweil uses the paradigm called Moore's Law to show that the singularity isn't just plausible but inevitable. Simply put, it states that the power of semiconductors doubles every two years. Engineers have repeatedly declared the end of this cycle, only to see computers grow more and more powerful. Turning to biology, Kurzweil notes that it took 15 years to sequence the HIV virus. In 2003 scientists took less than a month to sequence the newly emerged SARS virus.
Societies, meanwhile, are adopting technology more rapidly with each passing generation. Telephones required half a century to become ubiquitous; cell phones pulled off the same feat in just 8 years. As the time frame for such developments collapses, the advances themselves grow more disruptive, and their impact increases exponentially. "As leaders of companies, we're focused on the day-to-day, and we don't take time to pull back and think about the technologies that are going to rock our world," says Diamandis. "It's how automobiles caught buggy manufacturers blind."
Yet not everyone is convinced the world needs Singularity U. Prominent scientists have questioned many of Kurzweil's ideas—from the assumptions of exponential technological progress to the ability of neuroscientists to reverse-engineer such a complex a structure as the human brain. Some tech bloggers have derided the institute as a playground for Silicon Valley types with too much time and money. (A 10-day executive course is expected to cost $15,000.) On his CNET blog, tech analyst Peter Glaskowsky predicts the curriculum will be "a painful muddle of science and science fiction identifying no clear path to a future we might not even want."
Many take the endeavor seriously, however. Stephanie Langhoff, chief scientist at NASA Ames, signed up as a faculty adviser. And grad-student applications for this summer's pilot program have poured in from more than 60 countries, leaving administrators struggling to cull applicants. Lots of executives have expressed interest, too. Says Ismail: "If CEOs are not asking themselves big questions about how rapidly accelerating technologies apply to their business, you have to start asking them some questions."
Gibson is an editorial assistant with BusinessWeek.
Wednesday, April 01, 2009
Machines that can see
Without putting any ethical judgements on the implementations, this is a pretty exciting article (from last month's The Economist). The uses of computer vision is advancing rapidly and its really interesting how many real world uses its finding. Makes me think of Minority Report. Sure wouldn't want a job having a computer monitoring me though!! Check it out...
http://www.economist.com/science/tq/PrinterFriendly.cfm?story_id=13174409
Machines that can see
Mar 5th 2009
From The Economist print edition
Computing: Advances in computer-vision software are begetting a host of new ways for machines to view the world
Nick Dewar
ENSURING that employees wear warm smiles when helping customers is good business—but no easy task, even for attentive managers. Omron Corporation, a Japanese developer of robotics software, is concocting a solution. Its software can analyse digital images, including video, to recognise and classify facial expressions. Soon the company will start selling a “smile measurement” system that will alert managers—in real time, if desired—when a cashier fails to muster an adequate grin. The software is configurable, so employers will be able to decide just how happy their employees should appear.
Using computers to measure smiles will strike many as absurd. Yet machines are learning to see in increasingly reliable and useful ways, opening up a wide range of new applications. Indeed, computer vision, also known as object recognition, has developed so rapidly over the past few years that rather than struggling to make sense of what they see, computers can now outperform humans in some cases. Curiously enough, one such category is interpreting human facial expressions.
Venu Govindaraju, a computer scientist at the University of Buffalo in New York, is designing software that helps determine the authenticity of expressions. He found that expressions that take as much time to form as to fade away are more likely to be genuine than those with unequal “onset” and “offset” durations. Detecting phoniness this way is far from fail-safe, but it is a good guide. So good, in fact, that Unilever, an Anglo-Dutch consumer-goods giant, is using expression-analysis software to pinpoint how testers react to foods. Procter & Gamble, an American competitor, is using similar technology to decipher the expressions of focus groups viewing its advertisements.
Using computer vision to analyse how people react to advertising, combined with the ability to identify what sort of people they are, also provides new opportunities. Digital billboards—the large TV screens that display advertisements in public places—already take into account the weather (touting cold drinks when it is hot) and the time of day (promoting wine in the evening). NICTA, a media laboratory funded by the Australian government, has gone a stage further. It has developed a digital sign called TABANAR, which sports an integrated camera. When a passer-by approaches, software determines his sex, approximate age and hair growth. Shoppers can then be enticed with highly targeted advertisements: action figures for little boys, for example, or razors for beardless men. If the person begins to turn away, TABANAR launches a different ad, perhaps with dramatic music. If he comes back later, TABANAR can show yet another advertisement. “You tend to go: ‘Wow, thanks, how did you know I needed that?’,” says Rob Fitzpatrick of NICTA.
Computer vision can prevent sales, too. In Japan it recently became illegal to sell tobacco from vending machines without verifying that customers are at least 20 years old. Fujitaka, a maker of vending machines in Kyoto, promptly devised a solution: it built dispensers with artificial vision. Fujitaka’s new machines refuse to sell cigarettes if their software detects plumpness in the skin (a tell-tale sign of adolescence) around a potential customer’s eyes. Tests show that the system is slightly better at estimating people’s ages than nightclub bouncers are. Ray Chiang of Fujitaka says sales surged after the government certified the technique last year.
The elderly are also coming under scrutiny. Computer scientists at the Toronto Rehabilitation Institute in Canada have been testing a computer-vision system for monitoring people living in nursing homes or alone. A cheap camera, stuck to the ceiling, wirelessly relays images to a small computer that monitors how people move. When someone neglects to brush their teeth, flush the toilet or wash their hands, a speaker can prompt them to do so. And if a person falls over or stops moving, and fails to declare that all is well when prompted by the computer, the system calls a relative or dials an emergency number.
Watching while you work
Similar software can identify slackers in fast-food kitchens. This year HyperActive Technologies of Pittsburgh, Pennsylvania, is launching “HyperActive Bob”, a system that processes data collected by an array of cameras and alerts restaurant managers (either on site, or back at headquarters) when employees indulge in lengthy toilet breaks, or are slow to toss burgers onto the grill. The monitoring will be offered as a subscription, costing less than $200 a month for each restaurant.
Nello Zeuch, an independent consultant based in Yardley, Pennsylvania, says computer-vision systems are also being used to monitor products on assembly lines, as well as the workers assembling them. In car factories, for example, workers can be notified by vision systems if components are missing or improperly seated. In some cases, workers are warned if they reach for the wrong tool or part. In electronics factories vision technology has become a vital part of the testing process. A machine can examine a circuit board for faults almost instantly. A human would take far longer to do the same thing, and would be less accurate.
Computers no longer struggle to make sense of what they see, but can instead outperform humans.
Computer vision has even advanced to the point that it can perform internet searches with an image, rather than key words, as a search term. Later this year Accenture, a consulting firm, will launch a free service, called Accenture Mobile Object-Recognition Platform (AMORP), that will enable people to use images sent from mobile phones to look things up on the web. After sending an image of, say, a Chinese delicacy, a curious foodie might receive information gleaned from AsianFoodGrocer.com, for example. Fredrik Linaker, head of the AMORP project at Accenture’s research centre in Sofia Antipolis, France, likens the project to “physical-world hyperlinking”.
Microsoft is developing a competing service, known as Lincoln, which can already recognise more than a million objects in videos or photographs. Larry Zitnick, a Microsoft researcher in Redmond, Washington, notes that searching with images is often more precise than using words. Transmitting a picture of the Eiffel Tower taken from a magazine, for example, will fetch web pages that include information about travelling to Paris. Sending video footage of the monument itself, by contrast, will return web pages that contain useful information about the tower’s opening hours, or good places to eat nearby.
Sending pictures to the internet could help robots as well as people. Jim Little of the University of British Columbia in Canada wants to make robots less clumsy. He has connected robots wirelessly to the internet, enabling them to search for pictures online so that they can quickly learn to recognise nearby objects. Curious George, one of Dr Little’s robotic creations, can identify a book, for example, by finding a picture of it on Amazon, a leading online retailer.
One of the most promising uses of computer-vision software is in combating crime. In January a company called Evolution Robotics, based in Pasadena, California, began selling shopkeepers a system called LaneHawk InCart. When a customer arrives at a supermarket checkout, an overhead camera identifies the items on the conveyor belt and anything left behind in the shopping trolley. It then rings up the correct cost of the items. The system prevents “sweethearting”—the practice by which cashiers collude in a theft, either by failing to scan an item or by entering the wrong price. It also overcomes bar-code switching, in which would-be thieves remove the original bar-code and replace it with that of a cheaper item.
Eyes of the law
Nabbing drivers who switch car number-plates is another area where computer vision promises to help. Autonomy, a British firm, sells software that can recognise the make, model and colour of moving vehicles. By analysing data from roadside cameras, the system can notify police the moment a car drives past with a number-plate registered to another vehicle.
Similar technology is being used by repossession companies and other firms eager to get their hands on rogue vehicles. Last September Dijital Video ve Imge Teknolojileri, a firm based in Istanbul, launched a computer-vision system that uses a small camera mounted behind a car’s windscreen. A law firm installed it in 20 cars to look out for wanted vehicles and alert the police. Within two months it had led to the arrest of 15 drivers. They were “quite surprised”, says Muhittin Gökmen, the company’s founder. “They didn’t know they could be captured like this.”
Car-mounted vision systems can be used to prevent accidents as well as crime. The system sold by Mobileye Vision Technologies in Jerusalem, for example, notifies drivers of vehicles hidden in blind spots and advises them against changing lanes if speeding or erratically moving vehicles are nearby. The company has sold more than 100,000 systems to carmakers including BMW, General Motors and Volvo. This year Mobileye will launch a new system that applies the brakes if a collision is imminent.
The Technion-Israel Institute of Technology in Haifa, meanwhile, is developing roadside vision systems for dangerous junctions. If approaching cars appear to be heading towards a collision, drivers are warned by flashing street signs. Such safety systems need not be limited to roads. DFS Deutsche Flugsicherung, a government agency responsible for air-traffic control in Germany, is about to launch vision software for airports. Using images collected by surveillance cameras, its Advanced Surface Movement Guidance and Control System will warn traffic controllers of potential collisions between taxiing aircraft and vehicles ferrying luggage and food.
Jake Aggarwal, an expert in the security implications of traffic patterns at the University of Texas at Austin, is using funds from America’s defence department to analyse footage of suspicious driving filmed from above. Understanding vehicle movements, Mr Aggarwal says, is especially helpful to intelligence and security experts in Afghanistan and Iraq. Suspect vehicles include those that drive in circles and those that go to government buildings and military facilities, especially if they stop near them.
Advances in computer vision, in short, have applications in fields from advertising and manufacturing to road safety and counter-terrorism. It is a technology worth watching closely.
The World's Smallest Radio
I think this is more significant that some obscure article in Scientific American. The fact that a simple carbon nanotube can function as a complete radio (sans power and a speaker) is just plain wild. There are many great discoveries to unfold at the nano scale!
"A bare-bones radio, Zettl knew, has four essential parts: an antenna that picks up the electromagnetic signal; a tuner that selects the desired frequency from among all those being broadcast; an amplifier that increases the strength of the signal; and a demodulator that separates the informational signal from the carrier wave on which it is transmitted. The informational component is then sent to an external speaker, which turns that part of the signal into audible tones."
A single carbon nanotube can fullfill all of these - check it out!
Scientific American Magazine - March 9, 2009
The World's Smallest Radio
A single carbon nanotube can function as a radio that detects and plays songs
By Ed Regis
Nanotechnology is arguably one of the most overhyped “next big things” in the recent history of applied science. According to its most radical advocates, nanotechnology is a molecular manufacturing system that will allow us to fabricate objects of practically any arbitrary complexity by mechanically joining molecule to molecule, one after another, until the final, atomically correct product emerges before our eyes.
The reality has been somewhat different: today the word “nano” has been diluted to the point that it applies to essentially anything small, even down to the “nanoparticles” in commodities as diverse as motor oil, sunscreen, lipstick and ski wax. Who, then, would have expected that one of the first truly functional nanoscale devices—one that would have a measurable effect on the larger, macroscale world—would prove to be ... a radio? But the nanotube radio, invented in 2007 by physicist Alex Zettl and his colleagues at the University of California, Berkeley, performs a set of amazing feats: a single carbon nanotube tunes in a broadcast signal, amplifies it, converts it to an audio signal and then sends it to an external speaker in a form that the human ear can readily recognize. If you have any doubts about this assertion, just visit www.sciam.com/nanoradio and listen to the song “Layla.”
The nanotube radio, its fabricators say, could be the basis for a range of revolutionary applications: hearing aids, cell phones and iPods small enough to fit completely within the ear canal. The nanoradio “would easily fit inside a living cell,” Zettl says. “One can envision interfaces to brain or muscle functions or radio-controlled devices moving through the bloodstream.”
The Call of the Nanotube
Zettl, who directs 30 investigators engaged in creating molecular-scale devices, decided to make nanotubes a focus of his work because they are remarkable structures. The question of who first discovered them is controversial, but Japanese physicist Sumio Iijima is generally credited with having put them on the scientific map, when in 1991 he announced finding “needlelike tubes” of carbon on the tip of a graphite electrode that emitted an arc, a luminous discharge of electricity.
Those nanotubes had some surprising properties. They came in a large variety of sizes and shapes: they were single-walled, double-walled and multiwalled. Some were straight, some were bent and some even looped back on themselves in toroidal configurations. Common to them all was their exceptional tensile strength, the resistance to being pulled apart along their length without breaking. The reason for this unusual property, Zettl says, is that “the force that holds the carbon atoms together in the carbon nanotube is the strongest bond in nature.” Nanotubes are also excellent conductors of electricity, far better than copper, silver or even superconductors. “It’s because the electrons don’t hit anything,” he explains. “The tube is such a perfect structure.”
Zettl got the idea for a nanoradio when he decided he wanted to create tiny sensing devices that could communicate with one another and broadcast their observations wirelessly. “They were to do monitoring of environmental conditions,” he says. They would be distributed in the field near some factory or refinery and would radio their results back to some collecting point. Anyone could then go to Google “and click on the air quality of a city and see it in real time.” During the course of some experiments aimed at producing a nanotube mass sensor, one of Zettl’s graduate students, Kenneth Jensen, found that if one end of a carbon nanotube was planted on a surface, creating a cantilever, the beam would vibrate when a molecule landed on its free end. Molecules of different masses would make the beam vibrate at different frequencies. When Zettl noticed that some of these frequencies included those in the commercial radio band, the idea of using the cantilevered nanotube to make a radio became virtually irresistible.
A bare-bones radio, Zettl knew, has four essential parts: an antenna that picks up the electromagnetic signal; a tuner that selects the desired frequency from among all those being broadcast; an amplifier that increases the strength of the signal; and a demodulator that separates the informational signal from the carrier wave on which it is transmitted. The informational component is then sent to an external speaker, which turns that part of the signal into audible tones.
The carbon nanotube that was to be the core of the device proved to be a combination of such extremely favorable chemical, geometric and electrical properties that when it was placed between a set of electrodes, the miniature element alone accomplished all four functions simultaneously. No other parts were needed.
Zettl and Jensen began by working out an overall design in which a multiwalled carbon nanotube would be built on the tip of an electrode, an arrangement in which the nanotube would resemble a flagpole on a mountaintop. They decided on a multiwalled tube because it was a bit bigger than other kinds and was also easier to mount on the electrode surface, although they later constructed a version with a single-walled one as well. The tube, which would be about 500 nanometers long and 10 nanometers in diameter (roughly the size and shape of some viruses), would be placed on the electrode using nanomanipulation methods or directly grown on the electrode by a technique called chemical vapor deposition, in which layers of carbon precipitate out of an ionized gas.
Some distance away from the tip, rounded off in the shape of a hemispherical buckyball, would be a counterelectrode. A small direct-current (DC) voltage would be applied across the electrodes, creating a flow of electrons from the nanotube tip to the counterelectrode. The idea was that electromagnetic waves from an incoming radio transmission would impinge on the nanotube, causing it to physically vibrate in tune with the variations of the electromagnetic signal. Vibrating in sync with the incoming radio waves, the nanotube would be acting as an antenna but one that operates differently from that of a conventional radio.
In a normal radio, the antenna picks up incoming signals electronically, meaning that the incoming waves induce an electric current within the antenna, which remains stationary. In the nanoradio, in contrast, the nanotube is so slender and slight a charged object that the incoming electromagnetic waves are sufficient to push it back and forth mechanically.
“The nanoworld is weird—different things dominate,” Zettl describes. “Gravity plays no role whatsoever, and inertial effects are basically nonexistent because things are just so small that residual electrical fields can play a dominant role.”
The nanotube’s vibrations, in turn, would set up a change in the current flowing from the nanotube tip to the counterelectrode: technically a field-emission current. Field emission is a quantum-mechanical phenomenon in which a small applied voltage produces a large flow of electrons from the surface of an object—a needle tip, say. Because of the way field emission works, the nanotube was expected to function not only as an antenna but also as an amplifier.
The small-scale electromagnetic wave hitting the nanotube would cause a big spray of electrons to be released from its vibrating free end. That electron spray would amplify the incoming signal.
Next came demodulation, the process of separating a radio station’s carrier-wave frequency from the informational message—voice or music—that is coded on top of it. In an amplitude-modulation (AM) radio broadcast, for example, this separation is achieved by a rectification and filtering circuit that responds to the amplitude and ignores (filters out) the frequency of the carrier-wave signal. These functions, too, Zettl’s team reasoned, could be accomplished in the nanotube radio: when a nanotube mechanically vibrates in tune with a carrier wave’s frequency, it also responds to the coded informational wave. Fortunately, rectification is an inherent attribute of quantum-mechanical field emission, meaning that the current coming off the nanotube varies only with the coded or modulated informational wave, whereas the carrier wave drops out of the picture. It would be demodulation for free—no separate circuitry required.
In short, an incoming electromagnetic signal would cause the nanotube, now acting as an antenna, to vibrate. Its vibrating end would amplify the signal, and its field-emission property of built-in rectification would separate (or demodulate) the carrier wave from the informational wave. The counterelectrode would then detect the changes in the field-emission current and send a song or news broadcast to an audio loudspeaker, which would convert the signal into sound waves.
Doing the Experiment
That, anyway, was the theory. In January 2007 Zettl, Jensen and two other Berkeley researchers, Jeff Weldon and Henry Garcia, performed the actual experiment. They mounted a multiwalled carbon nanotube on a silicon electrode and placed a counterelectrode about a micron away, connecting the two by wire. They also attached a DC battery to the apparatus to set up a small field-emission current between the nanotube tip and the counterelectrode. To actually see what would happen during the course of a radio transmission from a nearby antenna, they placed their device inside a high-resolution transmission electron microscope (TEM). Then they started broadcasting.
According to the well-worn tale, the first message sent by telephone was the request, “Mr. Watson, come here. I want to see you,” spoken by Alexander Graham Bell in 1876. The first wireless transmission, sent by Guglielmo Marconi in 1894, was a radio wave that made a bell ring 30 feet away. And in January 2007 the first successful operation of Zettl’s carbon nanotube radio was the radio’s reception of the music for “Layla,” by Eric Clapton (while playing with Derek and the Dominos).
“It was fantastic,” Zettl recalls of the experience. “I mean, it was spectacular. We could watch the nanotube [in the TEM], and the fact that you could see this molecular structure vibrating and hear it at the same time is kind of cool. I never thought I could see a radio operate!”
You can see the results for yourself, because the experimenters documented the entire process—audio and video—and converted the recording to a QuickTime movie that they posted on the Zettl Group’s Web page, where anyone can download and play it for free. Later, they did the same with “Good Vibrations,” by the Beach Boys; the “Main Title” theme from Star Wars, by John Williams; and the largo from Xerxes, the opera by George Frideric Handel. “This is the first song ever transmitted using radio,” Zettl explains.
Hearing (and, yes, even watching) these tunes play is a surreal experience to witness. As the process starts up, a long, thin stationary nanotube appears against a featureless, grainy backdrop. The tube extends horizontally from a rocky-looking, irregular surface, next to a shorter nanotube that will remain untouched throughout by all the electromagnetic commotion taking place around it. (The shorter nanotube is insensitive to the broadcast because the frequency at which it resonates, which depends on its length, does not coincide with the frequency of the incoming transmission.)
Soon you hear a lot of static, but then the needle simply disappears in a vibrational blur as the song in question is dimly but recognizably heard above the background noise. It may sound like a broadcast from Neptune, but in fact it is the audible report of a countable number of carbon atoms moving in synchrony with the music.
Shortly after their initial success the experimenters removed the device from the TEM, made minor changes to the radio’s configuration, and then were able to both broadcast and receive signals across the length of the laboratory, a distance of a few meters. They were also able to tune in different frequencies in real time, in effect “changing the station” as the radio played.
A nanotube radio can be tuned in two separate ways. One is by changing its length. While you can change the tone of a guitar string by bending it down against different frets, you can change the resonance frequency of a nanotube by shortening it—for example, by boiling atoms off the tip.
That, change, however, is irreversible. But just as there is a second method of varying a guitar string’s pitch (namely, by varying its tension), so, too, with the nanotube. Varying the strength of the applied electric field will make the nanoradio respond to different frequencies of the radio band.
Their device did, in fact, perform all four of a radio’s functions simultaneously: it was an antenna, amplifier, demodulator and tuner—all in one. That such a small and simple structure combined all these functions continues to amaze Zettl. How does he explain their almost magical convergence in a single elongated molecule of carbon?
“In electronics, often you have a trade-off: if you optimize this, then you lose something else. Here everything seems to just work for you, which is a little unusual. You don’t see that often in science. It’s one of those rare opportunities to see Murphy’s Law not rearing its ugly head. Here everything that can go right is going right,” he says.
Zettl and his colleagues withheld news of the nanoradio for several months, until it could be published in Nano Letters, a journal of the American Chemical Society. The apparatus had its formal debut online in October 2007 and then in the November print edition. In that same print issue, two independent researchers, Chris Rutherglen and Peter Burke, both at the University of California, Irvine, announced the use of a carbon nanotube to demodulate an AM signal. They called their piece “Carbon Nanotube Radio,” but their radio was not an all-in-one device like Zettl’s. In Rutherglen and Burke’s setup, the antenna and amplification functions were provided by conventional, life-size desktop units. Burke, for his part, concedes that Zettl’s all-in-one radio is “very elegant.”
Lilliputian Drug Delivery Systems
Because it turns nanotechnology from a collection of theories, hopes and speculations into a practical, working appliance, the nanotube radio is potentially a transformative piece of equipment. Zettl, for one, is not bashful about foreseeing a bunch of killer apps made possible by the nanoradio: a whole new generation of communications devices, brain and muscle implants, and so on. Whereas some of these more futuristic applications will require a nontrivial amount of additional insight and engineering to make them into operational realities, others are more near term—in the form of radio-controlled drug delivery systems, for example.
One of the downsides of chemotherapy for shrinking invisible cancers that have spread or for treating inoperable ones is that the chemical agents used to kill cancer cells travel through the bloodstream to all parts of the body and often kill healthy cells as well as the malignant ones. A solution advanced by some physicians who have been in contact with Zettl would be to first inject packages that are molecularly targeted to cancer cells and that contain a chemo agent as well as a nanoradio; after allowing the packages time to find the tumors, radio-control signals would trigger release of the drug into the tumor cells for their destruction.
A second use would be to repair individual cells by injecting drugs into them. Zettl’s group has moved in this direction by working on a fine-scale approach to nanoinjection in which the researchers punctured cell walls and membranes and put nanotube structures inside, where they released specific chemicals.
“The cells withstand that very nicely,” Zettl says. “This nanoinjection technique works much better than the old technique where people used to try to use micropipettes that puncture cells and inject fluid. Those are way too crude and disruptive for most living cells.” Zettl also foresees an application of his original nanotube mass sensor. Some types of explosives contain signature molecules of a known mass, and so a minuscule instrument that detects those molecules rapidly and reliably could replace the refrigerator-size explosives-sensing mass spectrometers now in use at some airport security checkpoints. No one is commercializing any of these devices as yet. Zettl, however, has patented his nanoradio, the nano mass sensor and other inventions that have come out of his Center of Integrated Nanomechanical Systems and has begun licensing the technology for others to develop.
Perhaps not surprisingly, some of Zettl’s more recent achievements in the nanoworld seem to have plumbed the very limits of the Lilliputian. In July 2008 he announced in Nature that he and his group had coaxed an electron microscope to image individual atoms of hydrogen, nature’s smallest atom. In the downward direction, there is nowhere left to go.
Further Reading
Nanomedicine--Revolutionizing the Fight against Cancer
A Molecular Checkup: The Nano Future of Medicine
For Nanotech Drug Delivery, Size Doesn't Matter--Shape Does
Nanotech to Regrow Cartilage and Soothe Aching Knees
The Midas Touch: Using Gold Nanoparticles to Block HIV
Study Says Carbon Nanotubes as Dangerous as Asbestos
As Nanotech's Promise Grows, Will Puny Particles Present Big Health Problems?
For Remote-Control Cells, Just Add Magnets
"A bare-bones radio, Zettl knew, has four essential parts: an antenna that picks up the electromagnetic signal; a tuner that selects the desired frequency from among all those being broadcast; an amplifier that increases the strength of the signal; and a demodulator that separates the informational signal from the carrier wave on which it is transmitted. The informational component is then sent to an external speaker, which turns that part of the signal into audible tones."
A single carbon nanotube can fullfill all of these - check it out!
Scientific American Magazine - March 9, 2009
The World's Smallest Radio
A single carbon nanotube can function as a radio that detects and plays songs
By Ed Regis
Nanotechnology is arguably one of the most overhyped “next big things” in the recent history of applied science. According to its most radical advocates, nanotechnology is a molecular manufacturing system that will allow us to fabricate objects of practically any arbitrary complexity by mechanically joining molecule to molecule, one after another, until the final, atomically correct product emerges before our eyes.
The reality has been somewhat different: today the word “nano” has been diluted to the point that it applies to essentially anything small, even down to the “nanoparticles” in commodities as diverse as motor oil, sunscreen, lipstick and ski wax. Who, then, would have expected that one of the first truly functional nanoscale devices—one that would have a measurable effect on the larger, macroscale world—would prove to be ... a radio? But the nanotube radio, invented in 2007 by physicist Alex Zettl and his colleagues at the University of California, Berkeley, performs a set of amazing feats: a single carbon nanotube tunes in a broadcast signal, amplifies it, converts it to an audio signal and then sends it to an external speaker in a form that the human ear can readily recognize. If you have any doubts about this assertion, just visit www.sciam.com/nanoradio and listen to the song “Layla.”
The nanotube radio, its fabricators say, could be the basis for a range of revolutionary applications: hearing aids, cell phones and iPods small enough to fit completely within the ear canal. The nanoradio “would easily fit inside a living cell,” Zettl says. “One can envision interfaces to brain or muscle functions or radio-controlled devices moving through the bloodstream.”
The Call of the Nanotube
Zettl, who directs 30 investigators engaged in creating molecular-scale devices, decided to make nanotubes a focus of his work because they are remarkable structures. The question of who first discovered them is controversial, but Japanese physicist Sumio Iijima is generally credited with having put them on the scientific map, when in 1991 he announced finding “needlelike tubes” of carbon on the tip of a graphite electrode that emitted an arc, a luminous discharge of electricity.
Those nanotubes had some surprising properties. They came in a large variety of sizes and shapes: they were single-walled, double-walled and multiwalled. Some were straight, some were bent and some even looped back on themselves in toroidal configurations. Common to them all was their exceptional tensile strength, the resistance to being pulled apart along their length without breaking. The reason for this unusual property, Zettl says, is that “the force that holds the carbon atoms together in the carbon nanotube is the strongest bond in nature.” Nanotubes are also excellent conductors of electricity, far better than copper, silver or even superconductors. “It’s because the electrons don’t hit anything,” he explains. “The tube is such a perfect structure.”
Zettl got the idea for a nanoradio when he decided he wanted to create tiny sensing devices that could communicate with one another and broadcast their observations wirelessly. “They were to do monitoring of environmental conditions,” he says. They would be distributed in the field near some factory or refinery and would radio their results back to some collecting point. Anyone could then go to Google “and click on the air quality of a city and see it in real time.” During the course of some experiments aimed at producing a nanotube mass sensor, one of Zettl’s graduate students, Kenneth Jensen, found that if one end of a carbon nanotube was planted on a surface, creating a cantilever, the beam would vibrate when a molecule landed on its free end. Molecules of different masses would make the beam vibrate at different frequencies. When Zettl noticed that some of these frequencies included those in the commercial radio band, the idea of using the cantilevered nanotube to make a radio became virtually irresistible.
A bare-bones radio, Zettl knew, has four essential parts: an antenna that picks up the electromagnetic signal; a tuner that selects the desired frequency from among all those being broadcast; an amplifier that increases the strength of the signal; and a demodulator that separates the informational signal from the carrier wave on which it is transmitted. The informational component is then sent to an external speaker, which turns that part of the signal into audible tones.
The carbon nanotube that was to be the core of the device proved to be a combination of such extremely favorable chemical, geometric and electrical properties that when it was placed between a set of electrodes, the miniature element alone accomplished all four functions simultaneously. No other parts were needed.
Zettl and Jensen began by working out an overall design in which a multiwalled carbon nanotube would be built on the tip of an electrode, an arrangement in which the nanotube would resemble a flagpole on a mountaintop. They decided on a multiwalled tube because it was a bit bigger than other kinds and was also easier to mount on the electrode surface, although they later constructed a version with a single-walled one as well. The tube, which would be about 500 nanometers long and 10 nanometers in diameter (roughly the size and shape of some viruses), would be placed on the electrode using nanomanipulation methods or directly grown on the electrode by a technique called chemical vapor deposition, in which layers of carbon precipitate out of an ionized gas.
Some distance away from the tip, rounded off in the shape of a hemispherical buckyball, would be a counterelectrode. A small direct-current (DC) voltage would be applied across the electrodes, creating a flow of electrons from the nanotube tip to the counterelectrode. The idea was that electromagnetic waves from an incoming radio transmission would impinge on the nanotube, causing it to physically vibrate in tune with the variations of the electromagnetic signal. Vibrating in sync with the incoming radio waves, the nanotube would be acting as an antenna but one that operates differently from that of a conventional radio.
In a normal radio, the antenna picks up incoming signals electronically, meaning that the incoming waves induce an electric current within the antenna, which remains stationary. In the nanoradio, in contrast, the nanotube is so slender and slight a charged object that the incoming electromagnetic waves are sufficient to push it back and forth mechanically.
“The nanoworld is weird—different things dominate,” Zettl describes. “Gravity plays no role whatsoever, and inertial effects are basically nonexistent because things are just so small that residual electrical fields can play a dominant role.”
The nanotube’s vibrations, in turn, would set up a change in the current flowing from the nanotube tip to the counterelectrode: technically a field-emission current. Field emission is a quantum-mechanical phenomenon in which a small applied voltage produces a large flow of electrons from the surface of an object—a needle tip, say. Because of the way field emission works, the nanotube was expected to function not only as an antenna but also as an amplifier.
The small-scale electromagnetic wave hitting the nanotube would cause a big spray of electrons to be released from its vibrating free end. That electron spray would amplify the incoming signal.
Next came demodulation, the process of separating a radio station’s carrier-wave frequency from the informational message—voice or music—that is coded on top of it. In an amplitude-modulation (AM) radio broadcast, for example, this separation is achieved by a rectification and filtering circuit that responds to the amplitude and ignores (filters out) the frequency of the carrier-wave signal. These functions, too, Zettl’s team reasoned, could be accomplished in the nanotube radio: when a nanotube mechanically vibrates in tune with a carrier wave’s frequency, it also responds to the coded informational wave. Fortunately, rectification is an inherent attribute of quantum-mechanical field emission, meaning that the current coming off the nanotube varies only with the coded or modulated informational wave, whereas the carrier wave drops out of the picture. It would be demodulation for free—no separate circuitry required.
In short, an incoming electromagnetic signal would cause the nanotube, now acting as an antenna, to vibrate. Its vibrating end would amplify the signal, and its field-emission property of built-in rectification would separate (or demodulate) the carrier wave from the informational wave. The counterelectrode would then detect the changes in the field-emission current and send a song or news broadcast to an audio loudspeaker, which would convert the signal into sound waves.
Doing the Experiment
That, anyway, was the theory. In January 2007 Zettl, Jensen and two other Berkeley researchers, Jeff Weldon and Henry Garcia, performed the actual experiment. They mounted a multiwalled carbon nanotube on a silicon electrode and placed a counterelectrode about a micron away, connecting the two by wire. They also attached a DC battery to the apparatus to set up a small field-emission current between the nanotube tip and the counterelectrode. To actually see what would happen during the course of a radio transmission from a nearby antenna, they placed their device inside a high-resolution transmission electron microscope (TEM). Then they started broadcasting.
According to the well-worn tale, the first message sent by telephone was the request, “Mr. Watson, come here. I want to see you,” spoken by Alexander Graham Bell in 1876. The first wireless transmission, sent by Guglielmo Marconi in 1894, was a radio wave that made a bell ring 30 feet away. And in January 2007 the first successful operation of Zettl’s carbon nanotube radio was the radio’s reception of the music for “Layla,” by Eric Clapton (while playing with Derek and the Dominos).
“It was fantastic,” Zettl recalls of the experience. “I mean, it was spectacular. We could watch the nanotube [in the TEM], and the fact that you could see this molecular structure vibrating and hear it at the same time is kind of cool. I never thought I could see a radio operate!”
You can see the results for yourself, because the experimenters documented the entire process—audio and video—and converted the recording to a QuickTime movie that they posted on the Zettl Group’s Web page, where anyone can download and play it for free. Later, they did the same with “Good Vibrations,” by the Beach Boys; the “Main Title” theme from Star Wars, by John Williams; and the largo from Xerxes, the opera by George Frideric Handel. “This is the first song ever transmitted using radio,” Zettl explains.
Hearing (and, yes, even watching) these tunes play is a surreal experience to witness. As the process starts up, a long, thin stationary nanotube appears against a featureless, grainy backdrop. The tube extends horizontally from a rocky-looking, irregular surface, next to a shorter nanotube that will remain untouched throughout by all the electromagnetic commotion taking place around it. (The shorter nanotube is insensitive to the broadcast because the frequency at which it resonates, which depends on its length, does not coincide with the frequency of the incoming transmission.)
Soon you hear a lot of static, but then the needle simply disappears in a vibrational blur as the song in question is dimly but recognizably heard above the background noise. It may sound like a broadcast from Neptune, but in fact it is the audible report of a countable number of carbon atoms moving in synchrony with the music.
Shortly after their initial success the experimenters removed the device from the TEM, made minor changes to the radio’s configuration, and then were able to both broadcast and receive signals across the length of the laboratory, a distance of a few meters. They were also able to tune in different frequencies in real time, in effect “changing the station” as the radio played.
A nanotube radio can be tuned in two separate ways. One is by changing its length. While you can change the tone of a guitar string by bending it down against different frets, you can change the resonance frequency of a nanotube by shortening it—for example, by boiling atoms off the tip.
That, change, however, is irreversible. But just as there is a second method of varying a guitar string’s pitch (namely, by varying its tension), so, too, with the nanotube. Varying the strength of the applied electric field will make the nanoradio respond to different frequencies of the radio band.
Their device did, in fact, perform all four of a radio’s functions simultaneously: it was an antenna, amplifier, demodulator and tuner—all in one. That such a small and simple structure combined all these functions continues to amaze Zettl. How does he explain their almost magical convergence in a single elongated molecule of carbon?
“In electronics, often you have a trade-off: if you optimize this, then you lose something else. Here everything seems to just work for you, which is a little unusual. You don’t see that often in science. It’s one of those rare opportunities to see Murphy’s Law not rearing its ugly head. Here everything that can go right is going right,” he says.
Zettl and his colleagues withheld news of the nanoradio for several months, until it could be published in Nano Letters, a journal of the American Chemical Society. The apparatus had its formal debut online in October 2007 and then in the November print edition. In that same print issue, two independent researchers, Chris Rutherglen and Peter Burke, both at the University of California, Irvine, announced the use of a carbon nanotube to demodulate an AM signal. They called their piece “Carbon Nanotube Radio,” but their radio was not an all-in-one device like Zettl’s. In Rutherglen and Burke’s setup, the antenna and amplification functions were provided by conventional, life-size desktop units. Burke, for his part, concedes that Zettl’s all-in-one radio is “very elegant.”
Lilliputian Drug Delivery Systems
Because it turns nanotechnology from a collection of theories, hopes and speculations into a practical, working appliance, the nanotube radio is potentially a transformative piece of equipment. Zettl, for one, is not bashful about foreseeing a bunch of killer apps made possible by the nanoradio: a whole new generation of communications devices, brain and muscle implants, and so on. Whereas some of these more futuristic applications will require a nontrivial amount of additional insight and engineering to make them into operational realities, others are more near term—in the form of radio-controlled drug delivery systems, for example.
One of the downsides of chemotherapy for shrinking invisible cancers that have spread or for treating inoperable ones is that the chemical agents used to kill cancer cells travel through the bloodstream to all parts of the body and often kill healthy cells as well as the malignant ones. A solution advanced by some physicians who have been in contact with Zettl would be to first inject packages that are molecularly targeted to cancer cells and that contain a chemo agent as well as a nanoradio; after allowing the packages time to find the tumors, radio-control signals would trigger release of the drug into the tumor cells for their destruction.
A second use would be to repair individual cells by injecting drugs into them. Zettl’s group has moved in this direction by working on a fine-scale approach to nanoinjection in which the researchers punctured cell walls and membranes and put nanotube structures inside, where they released specific chemicals.
“The cells withstand that very nicely,” Zettl says. “This nanoinjection technique works much better than the old technique where people used to try to use micropipettes that puncture cells and inject fluid. Those are way too crude and disruptive for most living cells.” Zettl also foresees an application of his original nanotube mass sensor. Some types of explosives contain signature molecules of a known mass, and so a minuscule instrument that detects those molecules rapidly and reliably could replace the refrigerator-size explosives-sensing mass spectrometers now in use at some airport security checkpoints. No one is commercializing any of these devices as yet. Zettl, however, has patented his nanoradio, the nano mass sensor and other inventions that have come out of his Center of Integrated Nanomechanical Systems and has begun licensing the technology for others to develop.
Perhaps not surprisingly, some of Zettl’s more recent achievements in the nanoworld seem to have plumbed the very limits of the Lilliputian. In July 2008 he announced in Nature that he and his group had coaxed an electron microscope to image individual atoms of hydrogen, nature’s smallest atom. In the downward direction, there is nowhere left to go.
Further Reading
Nanomedicine--Revolutionizing the Fight against Cancer
A Molecular Checkup: The Nano Future of Medicine
For Nanotech Drug Delivery, Size Doesn't Matter--Shape Does
Nanotech to Regrow Cartilage and Soothe Aching Knees
The Midas Touch: Using Gold Nanoparticles to Block HIV
Study Says Carbon Nanotubes as Dangerous as Asbestos
As Nanotech's Promise Grows, Will Puny Particles Present Big Health Problems?
For Remote-Control Cells, Just Add Magnets
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