Institute of Electrical and Electronics Engineers

Posts Tagged ‘Institute of Electrical and Electronics Engineers’

University of Alberta (Canada) student nanorobotics team demonstrates potential medical technology in competitiion

Monday, May 6th, 2013

A University of Alberta (Canada) nanorobotics team has entered its nanobot system into the International Mobile Micro/nanorobotics Competition in Karlsruhe, Germany, as part of the ICRA Robot Challenges at the IEEE (Institute of Electrical and Electronics Engineers) International Conference on Robotics and Automation (ICRA) being held May 6 – 10, 2013 in Karlsruhe, Germany. From the May 6, 2013 news item on Nanowerk,

A team of engineering students is putting a twist on robotics, developing a nano-scale robotics system that could lead to new medical therapies.

In less than a year, the U of A team has assembled a working system that manipulates nano-scale ‘robots’. The team uses magnets to manipulate a droplet filled with iron oxide nanoparticles. Barely visible to the naked eye, the droplet measures 400-500 micrometres.

The May 3, 2013 University of Alberta news release by Richard Cairney, which originated the news item, describes the system,

Using a joystick, team members control the robot, making it travel along a specific route, navigate an obstacle course or to push micro-sized objects from one point to another.

The challenge is simple in concept but highly technical and challenging to execute: the team first injects a water droplet with iron oxide nanoparticles into into oil. The droplet holds its shape because it is encased in a surfactant—a soap-like formula that repels water on one side and attracts water on the other.

“It’s like a capsule,” said team member Yang Gao, who is working on her master’s degree in chemical engineering. “It’s a vehicle for the nanoparticles.”

The iron-filled droplet is placed in a playing ‘field’ measuring 2 x 3 millimetres. The team uses four magnets mounted each side of the rectangular field to move the droplet in a figure-8, manoeuvring it through four gates built into the field.

“We use the magnets to pull the droplet,” explains electrical engineering PhD student Remko van den Hurk.

In a second challenge, the team will be required to use the droplet as a bulldozer of sorts, to arrange micro-scale objects that measure 200 x 300 micrometres into a particular order on an even smaller playing field.

The competition has its serious side, these nanobots could one day be used in medical applications.

In the meantime there’s the competition, good luck!

Tags: Canada, ICRA, ICRA Robot Challenges, IEEE, Institute of Electrical and Electronics Engineers, International Conference on Robotics and Automation, International Mobile Micro/nanorobotics Competition, nanobots, Remko van den Hurk, Richard Cairney, University of Alberta, Yang Gao
Posted in medicine, nanotechnology | No Comments »

Skills training: get ready for the robots

Tuesday, February 12th, 2013

If the boffins at the Massachusetts Institute of Technology (MIT) are right, soon we may be learning alongside robots and using the same techniques. Helen Knight’s Feb. 11, 2013 news release for MIT highlights a recent study showing that robots, like humans, learn better if they cross-train. From the news release,

Robots are increasingly being used in the manufacturing industry to perform tasks that bring them into closer contact with humans. But while a great deal of work is being done to ensure robots and humans can operate safely side-by-side, more effort is needed to make robots smart enough to work effectively with people, says Julie Shah, an assistant professor of aeronautics and astronautics at MIT and head of the Interactive Robotics Group in the Computer Science and Artificial Intelligence Laboratory (CSAIL).

“People aren’t robots, they don’t do things the same way every single time,” Shah says. “And so there is a mismatch between the way we program robots to perform tasks in exactly the same way each time and what we need them to do if they are going to work in concert with people.”

Most existing research into making robots better team players is based on the concept of interactive reward, in which a human trainer gives a positive or negative response each time a robot performs a task.

However, human studies carried out by the military have shown that simply telling people they have done well or badly at a task is a very inefficient method of encouraging them to work well as a team.

Here’s the experiment Shah and her student performed,

So Shah and PhD student Stefanos Nikolaidis began to investigate whether techniques that have been shown to work well in training people could also be applied to mixed teams of humans and robots. One such technique, known as cross-training, sees team members swap roles with each other on given days. “This allows people to form a better idea of how their role affects their partner and how their partner’s role affects them,” Shah says.

In a paper to be presented at the International Conference on Human-Robot Interaction in Tokyo in March [2013], Shah and Nikolaidis will present the results of experiments they carried out with a mixed group of humans and robots, demonstrating that cross-training is an extremely effective team-building tool.

More specifically,

To allow robots to take part in the cross-training experiments, the pair first had to design a new algorithm to allow the devices to learn from their role-swapping experiences. So they modified existing reinforcement-learning algorithms to allow the robots to take in not only information from positive and negative rewards, but also information gained through demonstration. In this way, by watching their human counterparts switch roles to carry out their work, the robots were able to learn how the humans wanted them to perform the same task.

Each human-robot team then carried out a simulated task in a virtual environment, with half of the teams using the conventional interactive reward approach, and half using the cross-training technique of switching roles halfway through the session. Once the teams had completed this virtual training session, they were asked to carry out the task in the real world, but this time sticking to their own designated roles.

Shah and Nikolaidis found that the period in which human and robot were working at the same time — known as concurrent motion — increased by 71 percent in teams that had taken part in cross-training, compared to the interactive reward teams. They also found that the amount of time the humans spent doing nothing — while waiting for the robot to complete a stage of the task, for example — decreased by 41 percent.

What’s more, when the pair studied the robots themselves, they found that the learning algorithms recorded a much lower level of uncertainty about what their human teammate was likely to do next — a measure known as the entropy level — if they had been through cross-training.

Finally, when responding to a questionnaire after the experiment, human participants in cross-training were far more likely to say the robot had carried out the task according to their preferences than those in the reward-only group, and reported greater levels of trust in their robotic teammate. “This is the first evidence that human-robot teamwork is improved when a human and robot train together by switching roles, in a manner similar to effective human team training practices,” Nikolaidis says.

Shah believes this improvement in team performance could be due to the greater involvement of both parties in the cross-training process. “When the person trains the robot through reward it is one-way: The person says ‘good robot’ or the person says ‘bad robot,’ and it’s a very one-way passage of information,” Shah says. “But when you switch roles the person is better able to adapt to the robot’s capabilities and learn what it is likely to do, and so we think that it is adaptation on the person’s side that results in a better team performance.”

The work shows that strategies that are successful in improving interaction among humans can often do the same for humans and robots, says Kerstin Dautenhahn, a professor of artificial intelligence at the University of Hertfordshire in the U.K. “People easily attribute human characteristics to a robot and treat it socially, so it is not entirely surprising that this transfer from the human-human domain to the human-robot domain not only made the teamwork more efficient, but also enhanced the experience for the participants, in terms of trusting the robot,” Dautenhahn says.

The paper (Human-Robot Cross-Training: Computational Formulation, Modeling and Evaluation of a Human Team Training Strategy) written by Nikolaidis and Shah can be found here and the website for the conference (International Conference on Human-Robot Interaction [HRI]; 8th ACM [Association of Computing Machinery]/IEEE [Institute of Electrical and Electronics Engineers] Conference on Human-Robot Interaction) where it will be presented is here.

Tags: 8th ACM/IEEE Conference on Human-Robot Interaction, Association of Computing Machinery, cross-training, Helen Knight, HRI, Human-Robot Cross-Training: Computational Formulation Modeling and Evaluation of a Human Team Training Strategy, Institute of Electrical and Electronics Engineers, International Conference on Human-Robot Interaction, Julie Shah, Kerstin Dautenhahn, Massachusetts Institute of Technology, MIT, skills training, Stefanos Nikolaidis, University of Hertfordshire
Posted in robots | No Comments »

FrogHeart’s 2012, a selective roundup of my international online colleagues, and other bits

Monday, December 31st, 2012

This blog will be five years old in April 2013 and, sometime in January or February, the 2000th post will be published.

Statisticswise it’s been a tumultuous year for FrogHeart with ups and downs, thankfully ending on an up note. According to my AW stats, I started with 54,920 visits in January (which was a bit of an increase over December 2011. The numbers rose right through to March 2012 when the blog registered 68,360 visits and then the numbers fell and continued to fall. At the low point, this blog registered 45, 972 visits in June 2012 and managed to rise and fall through to Oct. 2012 when the visits rose to 54,520 visits. November 2012 was better with 66,854 visits and in December 2012 the blog will have received over 75,000 visits. (ETA Ja.2.13: This blog registered 81,0036 in December 2012 and an annual total of 681,055 visits.) Since I have no idea why the numbers fell or why they rose again, I have absolutely no idea what 2013 will bring in terms of statistics (the webalizer numbers reflect similar trends).

Interestingly and for the first time since I’ve activated the AW statistics package in Feb. 2009, the US ceased to be the primary source for visitors. As of April 2012, the British surged ahead for several months until November 2012 when the US regained the top spot only to lose it to China in December 2012.

Favourite topics according to the top 10 key terms included: nanocrystalline cellulose for Jan. – Oct. 2012 when for the first time in almost three years the topic fell out of the top 10; Jackson Pollock and physics also popped up in the top 10 in various months throughout the year; Clipperton Island (a sci/art project) has made intermittent appearances; SPAUN (Semantic Pointer Arichitecture Unified Network; a project at the University of Waterloo) has made the top 10 in the two months since it was announced); weirdly, frogheart.ca has appeared in the top 10 these last few months; the Lycurgus Cup, nanosilver, and literary tattoos also made appearances in the top 10 in various months throughout the year, while the memristor and Québec nanotechnology made appearances in the fall.

Webalizer tells a similar but not identical story. The numbers started with 83, 133 visits in January 2012 rising to a dizzying height of 119, 217 in March. These statistics fell too but July 2012 was another six figure month with 101,087 visits and then down again to five figures until Oct. 2012 with 108, 266 and 136,161 visits in November 2012. The December 2012 visits number appear to be dipping down slightly with 130,198 visits counted to 5:10 am PST, Dec. 31, 2012. (ETA Ja.2.13: In December 2012, 133,351 were tallied with an annual total of 1,660,771 visits.)

Thanks to my international colleagues who inspire and keep me apprised of the latest information on nanotechnology and other emerging technologies:

Pasco Phronesis, owned by David Bruggeman, focuses more on science policy and science communicati0n (via popular media) than on emerging technology per se but David provides excellent analysis and a keen eye for the international scene. He kindly dropped by frogheart.ca some months ago to challenge my take on science and censorship in Canada and I have not finished my response. I’ve posted part 1 in the comments but have yet to get to part 2. His latest posting on Dec. 30, 2012 features this title, For Better Science And Technology Policing, Don’t Forget The Archiving.
Nanoclast is on the IEEE (Institute of Electrical and Electronics Engineers) website and features Dexter Johnson’s writing on nanotechnology government initiatives, technical breakthroughs, and, occasionally, important personalities within the field. I notice Dexter, who’s always thoughtful and thought-provoking, has cut back to a weekly posting. I encourage you to read his work as he fills in an important gap in a lot of nanotechnology reporting with his intimate understanding of the technology itself. Dexter’s Dec. 20, 2012 posting (the latest) is titled, Nanoparticle Coated Lens Converts Light into Sound for Precise Non-invasive Surgery.
Insight (formerly TNTlog) is Tim Harper’s (CEO of Cientifica) blog features an international perspective (with a strong focus on the UK scene) on emerging technologies and the business of science. His writing style is quite lively (at times, trenchant) and it reflects his long experience with nanotechnology and other emerging technologies. I don’t know how he finds the time and here’s his latest, a Dec. 4, 2012 posting titled, Is Printable Graphene The Key To Widespread Applications?
2020 Science is Dr. Andrew Maynard’s (director of University of Michigan’s Risk Science Center) more or less personal blog. An expert on nanotechnology (he was the Chief Science Adviser for the Project on Emerging Nanotechnologies, located in Washington, DC), Andrew writes extensively about risk, uncertainty, nanotechnology, and the joys of science. Over time his blog has evolved to include the occasional homemade but science-oriented video, courtesy of one of his children. I usually check Andrew’s blog when there’s a online nanotechnology kerfuffle as he usually has the inside scoop. His latest posting on Dec. 23, 2012 features this title, On the benefits of wearing a hat while dancing naked, and other insights into the science of risk.
Andrew also produces and manages the Mind the Science Gap blog, which is a project encouraging MA students in the University of Michigan’s Public Health Program to write. Andrew has posted a summary of the last semester’s triumphs titled, Looking back at another semester of Mind The Science Gap.
NanoWiki is, strictly speaking, not a blog but the authors provide the best compilation of stories on nanotechnology issues and controversies that I have found yet. Here’s how they describe their work, “NanoWiki tracks the evolution of paradigms and discoveries in nanoscience and nanotechnology field, annotates and disseminates them, giving an overall view and feeds the essential public debate on nanotechnology and its practical applications.” There are also Spanish, Catalan, and mobile versions of NanoWiki. Their latest posting, dated Dec. 29, 2012, Nanotechnology shows we can innovate without economic growth, features some nanotechnology books.
In April 2012, I was contacted by Dorothée Browaeys about a French blog, Le Meilleur Des Nanomondes. Unfortunately, there doesn’t seem to have been much action there since Feb. 2010 but I’m delighted to hear from my European colleagues and hope to hear more from them.

Sadly, there was only one interview here this year but I think they call these things ‘a big get’ as the interview was with Vanessa Clive who manages the nanotechnology portfolio at Industry Canada. I did try to get an interview with Dr. Marie D’Iorio, the new Executive Director of Canada’s National Institute of Nanotechnology (NINT; BTW, the National Research Council has a brand new site consequently [since the NINT is a National Research Council agency, so does the NINT]), and experienced the same success I had with her predecessor, Dr. Nils Petersen.

I attended two conferences this year, S.NET (Society for the Study of Nanoscience and Emerging Technologies) 2012 meeting in Enschede, Holland where I presented on my work on memristors, artificial brains, and pop culture. The second conference I attended was in Calgary where I moderated a panel I’d organized on the topic of Canada’s science culture and policy for the 2012 Canadian Science Policy Conference.

There are a few items of note which appeared on the Canadian science scene. ScienceOnlineVancouver emerged in April 2012. From the About page,

ScienceOnlineVancouver is a monthly discussion series exploring how online communication and social media impact current scientific research and how the general public learns about it. ScienceOnlineVancouver is an ongoing discussion about online science, including science communication and available research tools, not a lecture series where scientists talk about their work. Follow the conversation on Twitter at @ScioVan, hashtag is #SoVan.

…

The concept of these monthly meetings originated in New York with SoNYC @S_O_NYC, brought to life by Lou Woodley (@LouWoodley, Communities Specialist at Nature.com) and John Timmer (@j_timmer, Science Editor at Ars Technica). With the success of that discussion series, participation in Scio2012, and the 2012 annual meeting of the AAAS in Vancouver, Catherine Anderson, Sarah Chow, and Peter Newbury were inspired to bring it closer to home, leading to the beginning of ScienceOnlineVancouver.

ScienceOnlineVancouver is part of the ScienceOnlineNOW community that includes ScienceOnlineBayArea, @sciobayarea and ScienceOnlineSeattle, @scioSEA. Thanks to Brian Glanz of the Open Science Federation and SciFund Challenge and thanks to Science World for a great venue.

I have mentioned the arts/engineering festival coming up in Calgary, Beakerhead, a few times but haven’t had occasion to mention Science Rendezvous before. This festival started in Toronto in 2008 and became a national festival in 2012 (?). Their About page doesn’t describe the genesis of the ‘national’ aspect to this festival as clearly as I would like. They seem to be behind with their planning as there’s no mention of the 2013 festival,which should be coming up in May.

The twitter (@frogheart) feed continues to grow in both (followed and following) albeit slowly. I have to give special props to @carlacap, @cientifica, & @timharper for their mentions, retweets, and more.

As for 2013, there are likely to be some changes here; I haven’t yet decided what changes but I will keep you posted. Have a lovely new year and I wish you all the best in 2013.

Tags: 2012 S.NET Annual Meeting, 2020 Science, @carlacap, Andrew Maynard, Beakerhead, Cientifica, David Bruggeman, Dexter Johnson, Dorothée Browaeys, IEEE, Insight, Institute of Electrical and Electronics Engineers, Le Meilleur Des Nanomondes, Mind the Science Gap, Nanoclast, Nanowiki, Pasco Phronesis, Science Rendezvous, ScienceOnlineVancouver, Tim Harper, Twitter, Vanessa Clive
Posted in science communication | 2 Comments »

Breakthroughs with self-assembling DNA-based nanoscaled structures

Wednesday, December 19th, 2012

With all the talk about self-assembling DNA nanotechnology, it’s possible to misunderstand the stage of development this endeavour occupies as the title, Reality check for DNA Nanotechnology, for a Dec. 13, 2012 news release on EurekAlert suggests,

… This emerging technology employs DNA as a programmable building material for self-assembled, nanometer-scale structures. Many practical applications have been envisioned, and researchers recently demonstrated a synthetic membrane channel made from DNA. Until now, however, design processes were hobbled by a lack of structural feedback. Assembly was slow and often of poor quality.

In fact, the news release is touting two breakthroughs,

Now researchers led by Prof. Hendrik Dietz of the Technische Universitaet Muenchen (TUM) have removed these obstacles.

One barrier holding the field back was an unproven assumption. Researchers were able to design a wide variety of discrete objects and specify exactly how DNA strands should zip together and fold into the desired shapes. They could show that the resulting nanostructures closely matched the designs. Still lacking, though, was the validation of the assumed subnanometer-scale precise positional control. This has been confirmed for the first time through analysis of a test object designed specifically for the purpose. A technical breakthrough based on advances in fundamental understanding, this demonstration has provided a crucial reality check for DNA nanotechnology.

In a separate set of experiments, the researchers discovered that the time it takes to make a batch of complex DNA-based objects can be cut from a week to a matter of minutes, and that the yield can be nearly 100%. They showed for the first time that at a constant temperature, hundreds of DNA strands can fold cooperatively to form an object — correctly, as designed — within minutes. Surprisingly, they say, the process is similar to protein folding, despite significant chemical and structural differences. “Seeing this combination of rapid folding and high yield,” Dietz says, “we have a stronger sense than ever that DNA nanotechnology could lead to a new kind of manufacturing, with a commercial, even industrial future.” And there are immediate benefits, he adds: “Now we don’t have to wait a week for feedback on an experimental design, and multi-step assembly processes have suddenly become so much more practical.”

Dexter Johnson comments in his Dec. 18, 2012 posting (which includes an embedded video) on the Nanoclast blog (located on the Institute of Electrical and Electronics Engineers [IEEE] website),

The field of atomically precise manufacturing—or molecular manufacturing—has taken a big step towards realizing its promise with this latest research. We may still be a long way from realizing the “nanotech rapture” but certainly knowing that the objects built meet their design specifications and can be produced in minutes rather than weeks has to be recognized as a significant development.

Three papers have been published on these breakthroughs, here are the citations,

Xiao-chen Bai, Thomas G. Martin, Sjors H. W. Scheres, Hendrik Dietz. Cryo-EM structure of a 3D DNA-origami object. Proceedings of the National Academy of Sciences of the USA, Dec. 4, 2012, 109 (49) 20012-20017; on-line in PNAS Early Edition, Nov. 19, 2012. DOI: 10.1073/pnas.1215713109

Jean-Philippe J. Sobczak, Thomas G. Martin, Thomas Gerling, Hendrik Dietz. Rapid folding of DNA into nanoscale shapes at constant temperature. Science, vol. 338, issue 6113, pp. 1458-1461. DOI: 10.1126/science.1229919

See also: Martin Langecker, Vera Arnaut, Thomas G. Martin, Jonathan List, Stephan Renner, Michael Mayer, Hendrik Dietz, and Friedrich C. Simmel. Synthetic lipid membrane channels formed by designed DNA nanostructures. Science, vol. 338, issue 6109, pp. 932-936. DOI: 10.1126/science.1225624

Tags: Cryo-EM structure of a 3D DNA-origami object, Dexter Johnson, DNA nanotechnology, Friedrich C. Simme, Hendrik Dietz, IEEE, Institute of Electrical and Electronics Engineers, Jean-Philippe J. Sobczak, Jonathan List, manufacturing, Martin Langecker, Michael Mayer, Rapid folding of DNA into nanoscale shapes at constant temperature, Sjors H. W. Scheres, Stephan Renner, Synthetic lipid membrane channels formed by designed DNA nanostructures, Technische Universitaet Muenchen, Thomas G. Martin, Thomas Gerling, TUM, Vera Arnaut, Xiao-chen Bai
Posted in nanotechnology | No Comments »

Mad about Madder in lithium-ion batteries

Wednesday, December 12th, 2012

It hasn’t happened yet but it looks like the future might hold greener lithium-ion (Li-ion) batteries. According to the Dec. 11, 2012 news release on EurekAlert,

Scientists at Rice University and the City College of New York have discovered that the madder plant, aka Rubia tinctorum, is a good source of purpurin, an organic dye that can be turned into a highly effective, natural cathode for lithium-ion batteries. The plant has been used since ancient times to create dye for fabrics.

…

The goal, according to lead author Arava Leela Mohana Reddy, a research scientist in the Rice lab of materials scientist Pulickel Ajayan, is to create environmentally friendly batteries that solve many of the problems with lithium-ion batteries in use today.

Purpurin, left, extracted from madder root, center, is chemically lithiated, right, for use as an organic cathode in batteries. The material was developed as a less expensive, easier-to-recycle alternative to cobalt oxide cathodes now used in lithium-ion batteries. Credit: Ajayan Lab/Rice University

The Dec. 11, 2012 Rice University news release by Mike Williams, the origin for the one on EurekAlert, describes why the researchers are so interested in a more environmentally-friendly cathode,

While lithium-ion batteries have become standard in conventional electronics since their commercial introduction in 1991, the rechargeable units remain costly to manufacture, Reddy said. “They’re not environmentally friendly. They use cathodes of lithium cobalt oxide, which are very expensive. You have to mine the cobalt metal and manufacture the cathodes in a high-temperature environment. There are a lot of costs.

“And then, recycling is a big issue,” he said. “In 2010, almost 10 billion lithium-ion batteries had to be recycled, which uses a lot of energy. Extracting cobalt from the batteries is an expensive process.”

Reddy and his colleagues came across purpurin while testing a number of organic molecules for their ability to electrochemically interact with lithium and found purpurin most amenable to binding lithium ions. With the addition of 20 percent carbon to add conductivity, the team built a half-battery cell with a capacity of 90 milliamp hours per gram after 50 charge/discharge cycles. The cathodes can be made at room temperature, he said.

“It’s a new mechanism we are proposing with this paper, and the chemistry is really simple,” Reddy said. He suggested agricultural waste may be a source of purpurin, as may other suitable molecules, which makes the process even more economical.

Innovation in the battery space is needed to satisfy future demands and counter environmental issues like waste management, “and hence we are quite fascinated by the ability to develop alternative electrode technologies to replace conventional inorganic materials in lithium-ion batteries,” said Ajayan, Rice’s Benjamin M. and Mary Greenwood Anderson Professor in Mechanical Engineering and Materials Science and of chemistry.

“We’re interested in developing value-added chemicals, products and materials from renewable feedstocks as a sustainable technology platform,” said co-lead author George John, a professor of chemistry at the City College of New York-CUNY and an expert on bio-based materials and green chemistry. “The point has been to understand the chemistry between lithium ions and the organic molecules. Now that we have that proper understanding, we can tap other molecules and improve capacity.”

For anyone who’s interested, you can read the researchers’ article (open access),

Lithium storage mechanisms in purpurin based organic lithium ion battery electrodes by Arava Leela Mohana Reddy, Subbiah Nagarajan, Porramate Chumyim, Sanketh R. Gowda, Padmanava Pradhan, Swapnil R. Jadhav, Madan Dubey, George John & Pulickel M. Ajayan in Scientific Reports 2 Article number: 960 doi:10.1038/srep00960

You might also want to check out Dexter Johnson’s Nov. 26, 2012 posting (on Nanoclast, an IEEE [Institute of Electrical and Electronics Engineers] blog)where he mentions a technical deficiency (recharging becomes increasingly difficult) with the current Li-ion batteries in the context of his description of a new imaging technique.

Tags: Arava Leela Mohana Reddy, City College of New York, Dexter Johnson, George John, IEEE, Institute of Electrical and Electronics Engineers, li-ion batteries, lithium-ion batteries, Madan Dubey, madder plant, Padmanava Pradhan, Porramate Chumyim, Pulickel M. Ajayan, purpurin, Rice University, Rubia tinctorum, Sanketh R. Gowda, Subbiah Nagarajan, Swapnil R. Jadhav
Posted in Uncategorized | 1 Comment »

Christmas-tree shaped ’4-D’ nanowires

Wednesday, December 5th, 2012

This Dec. 5, 2012 news item on Nanowerk features a seasonal approach to a study about ’4-D’ nanowires,

A new type of transistor shaped like a Christmas tree has arrived just in time for the holidays, but the prototype won’t be nestled under the tree along with the other gifts.

“It’s a preview of things to come in the semiconductor industry,” said Peide “Peter” Ye, a professor of electrical and computer engineering at Purdue University.

Researchers from Purdue and Harvard universities created the transistor, which is made from a material that could replace silicon within a decade. Each transistor contains three tiny nanowires made not of silicon, like conventional transistors, but from a material called indium-gallium-arsenide. The three nanowires are progressively smaller, yielding a tapered cross section resembling a Christmas tree.

Sadly, Purdue University (Indiana, US) will not be releasing any images to accompany their Dec. 4, 2012 news release (which originated the news item) about the ’4-D’ transistor until Saturday, Dec. 8, 2012. So here’s an image of a real Christmas tree from the National Christmas Tree Organization’s Common Tree Characteristics webpage,

Douglas Fir Christmas tree from http://www.realchristmastrees.org/dnn/AllAboutTrees/TreeCharacteristics.aspx

The Purdue University news release written by Emil Venere provides more detail about the work,

“A one-story house can hold so many people, but more floors, more people, and it’s the same thing with transistors,” Ye said. “Stacking them results in more current and much faster operation for high-speed computing. This adds a whole new dimension, so I call them 4-D.”

…

The work is led by Purdue doctoral student Jiangjiang Gu and Harvard postdoctoral researcher Xinwei Wang.

The newest generation of silicon computer chips, introduced this year, contain transistors having a vertical 3-D structure instead of a conventional flat design. However, because silicon has a limited “electron mobility” – how fast electrons flow – other materials will likely be needed soon to continue advancing transistors with this 3-D approach, Ye said.

Indium-gallium-arsenide is among several promising semiconductors being studied to replace silicon. Such semiconductors are called III-V materials because they combine elements from the third and fifth groups of the periodic table.

…

Transistors contain critical components called gates, which enable the devices to switch on and off and to direct the flow of electrical current. Smaller gates make faster operation possible. In today’s 3-D silicon transistors, the length of these gates is about 22 nanometers, or billionths of a meter.

The 3-D design is critical because gate lengths of 22 nanometers and smaller do not work well in a flat transistor architecture. Engineers are working to develop transistors that use even smaller gate lengths; 14 nanometers are expected by 2015, and 10 nanometers by 2018.

However, size reductions beyond 10 nanometers and additional performance improvements are likely not possible using silicon, meaning new materials will be needed to continue progress, Ye said.

Creating smaller transistors also will require finding a new type of insulating, or “dielectric” layer that allows the gate to switch off. As gate lengths shrink smaller than 14 nanometers, the dielectric used in conventional transistors fails to perform properly and is said to “leak” electrical charge when the transistor is turned off.

Nanowires in the new transistors are coated with a different type of composite insulator, a 4-nanometer-thick layer of lanthanum aluminate with an ultrathin, half-nanometer layer of aluminum oxide. The new ultrathin dielectric allowed researchers to create transistors made of indium-gallium- arsenide with 20-nanometer gates, which is a milestone, Ye said.

This work will be presented at the 2012 International Electron Devices (IEEE [Institute of Electrical and Electronics Engineers]) meeting in San Francisco, California, Dec. 10 – 12, 2012 (as per the information on the registration page) with the two papers written by the team will be published in the proceedings.

I have a full list of the authors, from the news release,

The authors of the research papers are Gu [Jiangjiang Gu]; Wang [Xinwei Wang]; Purdue doctoral student H. Wu; Purdue postdoctoral research associate J. Shao; Purdue doctoral student A. T. Neal; Michael J. Manfra, Purdue’s William F. and Patty J. Miller Associate Professor of Physics; Roy Gordon, Harvard’s Thomas D. Cabot Professor of Chemistry; and Ye [Peide "Peter" Ye].

Tags: 2012 IEDM, 2012 International Electron Devices meeting, 4-D transistors, A. T. Neal, Christmas tree shape, Emil Venere, H.Wu, Harvard University, IEEE, Institute of Electrical and Electronics Engineers, J. Shao, Jiangjiang Gu, Michael J. Manfra, nanoelectronics, nanowires, Patty J. Miller, Peide "Peter" Ye, Purdue University, Roy Gordon, Thomas D. Cabot, William F. Miller, Xinwei Wang
Posted in electronics, nanotechnology | No Comments »

Graphene, replacing silicon, and epitaxial growth

Monday, October 1st, 2012

Researchers in Norway have created a semiconductor on a graphene substrate—absolutely no silicon in the substrate. From the Sept. 28, 2012 news item on Nanowerk,

Norwegian researchers are the world’s first to develop a method for producing semiconductors from graphene. This finding may revolutionise the technology industry.
The method involves growing semiconductor-nanowires on graphene. To achieve this, researchers “bomb” the graphene surface with gallium atoms and arsenic molecules, thereby creating a network of minute nanowires.
The result is a one-micrometre thick hybrid material which acts as a semiconductor. By comparison, the silicon semiconductors in use today are several hundred times thicker. The semiconductors’ ability to conduct electricity may be affected by temperature, light or the addition of other atoms.

The Research Council of Norway’s Sept.28, 2012 news release, which originated the news item, offers this,

Graphene is the thinnest material known, and at the same time one of the strongest. It consists of a single layer of carbon atoms and is both pliable and transparent. The material conducts electricity and heat very effectively. And perhaps most importantly, it is very inexpensive to produce.

“Given that it’s possible to make semiconductors out of graphene instead of silicon, we can make semiconductor components that are both cheaper and more effective than the ones currently on the market,” explains Helge Weman of the Norwegian University of Science and Technology (NTNU). Dr Weman is behind the breakthrough discovery along with Professor Bjørn-Ove Fimland.

“A material comprising a pliable base that is also transparent opens up a world of opportunities, one we have barely touched the surface of,” says Dr Weman. “This may bring about a revolution in the production of solar cells and LED components. Windows in traditional houses could double as solar panels or a TV screen. Mobile phone screens could be wrapped around the wrist like a watch. In short, the potential is tremendous.”

The researchers have patented this work and founded a startup company, CrayoNano. They provide a video animation of the process,

The narrator mentions epataxial growth and the gallium arsenide nanowires being grown on the graphene substrate. For anyone not familiar with ‘epataxial growth’, I found a definition in another Sept. 28, 2012 news item about graphene research on Nanowerk,

One of the best ways of producing high quality graphene is to grow it epitaxially (in layers) from crystals of silicon carbide. For use in electronic devices, it is important to be able to count the number of graphene layers that are grown, as single and double layers of graphene have different electrical properties.

This research out of the UK is based on using silicon as a substrate and you can find out more (excerpted from the news item about the National Physical Laboratory’s graphene research on Nanowerk),

Recent National Physical Laboratory research, published in the Journal of Applied Physics (“Identification of epitaxial graphene domains and adsorbed species in ambient conditions using quantified topography measurements” [open access]), looked at different topography approaches of determining graphene thickness and investigated the factors that can influence the accuracy of the results, such as atmospheric water and other adsorbates on the graphene surface.

Getting back to graphene substrates, the Research Council of Norway’s news release provides the reminder that this research is about business,

The researchers will now begin to create prototypes directed towards specific areas of application. They have been in contact with giants in the electronics industry such as Samsung and IBM. “There is tremendous interest in producing semiconductors out of graphene, so it shouldn’t be difficult to find collaborative partners,” Dr Weman adds.

The researchers are hoping to have the new semiconductor hybrid materials on the commercial market in roughly five years.

Dexter Johnson in a Sept. 28, 2012 posting on his Nanoclast blog, which is hosted by the IEEE (Institute of Electrical and Electronics Engineers), provides some business perspective,

Weman notes: “Companies like IBM and Samsung are driving this development in the search for a replacement for silicon in electronics as well as for new applications, such as flexible touch screens for mobile phones. Well, they need not wait any more. Our invention fits perfectly with the production machinery they already have. We make it easy for them to upgrade consumer electronics to a level where design has no limits.”

As magnanimous as Weman’s invitation sounds, one can’t help but think it comes from concern. The prospect of a five-year-development period before a product gets to market might be somewhat worrying for a group of scientists who just launched a new startup. A nice licensing agreement from one of the big electronics companies must look appealing right about now.

Tags: Bjørn-Ove Fimland, CrayoNano, Dexter Johnson, epataxial growth, gallium arsenide nanowires, graphene, Helge Weman, IBM, Identification of epitaxial graphene domains and adsorbed species in ambient conditions using quantified topography measurements, IEEE, Institute of Electrical and Electronics Engineers, Norway, Norwegian University of Science and Technology, NTNU, Research Council of Norway, Samsung, UK National Physical Laboratory
Posted in electronics, nanotechnology | No Comments »

Where do buckyballs come from?

Tuesday, August 7th, 2012

I’ve always wondered where buckyballs come from (as have scientists for the last 25 years) and now there’s an answer of sorts (from the July 31, 2012 Florida State University news release Note: I have removed some links),

“We started with a paste of pre-existing fullerene molecules mixed with carbon and helium, shot it with a laser, and instead of destroying the fullerenes we were surprised to find they’d actually grown,” they wrote. The fullerenes were able to absorb and incorporate carbon from the surrounding gas.

By using fullenes that contained heavy metal atoms in their centers, the scientists showed that the carbon cages remained closed throughout the process.

“If the cages grew by splitting open, we would have lost the metal atoms, but they always stayed locked inside,” Dunk [Paul Dunk, a doctoral student in chemistry and biochemistry at Florida State and lead author of the study published in Nature Communications] noted.

The researchers worked with a team of MagLab chemists using the lab’s 9.4-tesla Fourier transform ion cyclotron resonance mass spectrometer to analyze the dozens of molecular species produced when they shot the fullerene paste with the laser. The instrument works by separating molecules according to their masses, allowing the researchers to identify the types and numbers of atoms in each molecule. The process is used for applications as diverse as identifying oil spills, biomarkers and protein structures.

Dexter Johnson in his Aug. 6, 2012 posting on the Nanoclast blog on the IEEE (Institute of Electrical and Electronics Engineers) provides some context and commentary (Note: I have removed a link),

When Richard Smalley, Robert Curl, James Heath, Sean O’Brien, and Harold Kroto prepared the first buckminsterfullerene (C60) (or buckyball), they kicked off the next 25 years of nanomaterial science.

Here’s an artist’s illustration of what these scientists have achieved, fullerene cage growth,

An artist’s representation of fullerene cage growth via carbon absorption from surrounding hot gases. Some of the cages contain lanthanum metal atoms. (Image courtesy National Science Foundation) [downloaded from Florida State University website]

As I noted earlier I’m not alone in my fascination (from the news release),

Many people know the buckyball, also known by scientists as buckminsterfullerene, carbon 60 or C60, from the covers of their school chemistry textbooks. Indeed, the molecule represents the iconic image of “chemistry.” But how these often highly symmetrical, beautiful molecules with fascinating properties form in the first place has been a mystery for a quarter-century. Despite worldwide investigation since the 1985 discovery of C60, buckminsterfullerene and other, non-spherical C60 molecules — known collectively as fullerenes — have kept their secrets. How? They’re born under highly energetic conditions and grow ultra-fast, making them difficult to analyze.

“The difficulty with fullerene formation is that the process is literally over in a flash — it’s next to impossible to see how the magic trick of their growth was performed,” said Paul Dunk, a doctoral student in chemistry and biochemistry at Florida State and lead author of the work.

There’s more than just idle curiosity at work (from the news release),

The buckyball research results will be important for understanding fullerene formation in extraterrestrial environments. Recent reports by NASA showed that crystals of C60 are in orbit around distant suns. This suggests that fullerenes may be more common in the universe than previously thought.

“The results of our study will surely be extremely valuable in deciphering fullerene formation in extraterrestrial environments,” said Florida State’s Harry Kroto, a Nobel Prize winner for the discovery of C60 and co-author of the current study.

The results also provide fundamental insight into self-assembly of other technologically important carbon nanomaterials such as nanotubes and the new wunderkind of the carbon family, graphene.

H/T to Nanowerk’s July 31, 2012 news item titled, Decades-old mystery how buckyballs form has been solved. In addition to Florida State University, National High Magnetic Field Laboratory (or MagLab), the CNRS (Centre National de la Recherche Scientifique)Institute of Materials in France and Nagoya University in Japan were also involved in the research.

Tags: buckminster fullerenes, buckyballs, C60, carbon 60, carbon nanotubes, Centre National de la Recherche Scientifique, CNRS, Dexter Johnson, Florida State University, France, fullerenes, graphene, IEEE, Institute of Electrical and Electronics Engineers, Japan, MagLab, Nagoya University, National High Magnetic Field Laboratory, Paul Dunk, Sir Harold Kroto
Posted in nanotechnology, space exploration | No Comments »

Sustainable nano society?

Monday, June 18th, 2012

There’s a new nanotechnology organization according to the June 15, 2012 news item on Nanowerk,

Nanotechnology has a window of opportunity to aid in the sustainability of the planet. A group of scientists and engineers has recognized this remarkable chance to raise up a sustainable industry while helping sustain the environment, economy and society. The Sustainable Nanotechnology Organization (SNO) promotes research, education, and responsibility to fulfill its mission.

The first meeting, November 4-6, 2012, in Washington DC features plenaries by Nobelist Sir Harry Kroto and National Nanotechnology Initiative founding father, Mihail (Mike) Roco and over 100 individual presentations.

Here’s more about the Sustainable Nanotechnology Organization, from the home page,

The Sustainable Nanotechnology Organization (SNO) is a non-profit, worldwide professional society comprised of individuals and institutions that are engaged in:

Research and development of sustainable nanotechnology

Implications of nanotechnology for Environment, Health, and Safety

Advances in nanoscience, methods, protocols and metrology

Education and understanding of sustainable nanotechnology

Applications of nanotechnology for sustainability

SNO’s purpose is to provide a professional society forum to advance knowledge in all aspects of sustainable nanotechnology, including both applications and implications.

I find Roco’s involvement in the Nov. 2012 meeting interesting in light of some comments Dexter Johnson made in his June 8, 2 012 posting on Nanoclast (on the IEEE [Institute of Electrical and Electronics Engineers]) about Roco’s current campaign to encourage international nanotechnology research cooperation (Note: I have removed links from the excerpt),

Roco was the man behind turning a scattering of papers in condensed matter/solid state physics or chemistry into a national initiative. In doing so, he unwittingly—or not—launched an international nanotechnology arms race, which has seen at least 35 countries jump on to the bandwagon since the NNI was started.

Make no mistake, this “race” is no joke. There are billions of dollars at stake and national reputations seem to be built up on success in crossing the vague finish line before some other country.

…

So after unleashing this billion-dollar nanotech arms race, Roco now is urging collaboration in nanotech to provide the push the field needs to progress.

…

Well, yes, of course, and it’s about time somebody said it. It probably couldn’t have come from a better source either.

Dexter provides some good insight into the impact Roco has had on nanotechnology research in the US and internationally and, personally, I find these new developments quite fascinating.

Tags: Dexter Johnson, IEEE, Institute of Electrical and Electronics Engineers, Mihail Roco, NNI, Sir Harry Kroto, SNO, sustainability, Sustainable Nanotechnology Organization, US National Nanotechnology Initiative
Posted in nanotechnology | 1 Comment »

FrogHeart