Boosting creativity with interactive technology
October 4, 2011
Researchers at the University of Gothenburg show that interactive technology generates new ways of seeing, showing and creating. The new technology boosts creativity.
Jonas Ivarsson, Docent (Reader) at the Department of Education, Communication and Learning at the University of Gothenburg, has used students of architecture to study how new tools affect the specific abilities students develop in school. Within the research project Studying learning and representational technologies in design, supported by the Swedish Research Council, Ivarsson observed and video documented the students’ progress. He analysed their speech, gestures and tools, as well as the many objects they used.
‘The results of their work are in many ways similar to those of previous generations, but the work process has changed significantly,’ says Ivarsson.
New design process
Modern computer technology makes it possible to test new design ideas with a very high level of visual realism.
‘It has changed the entire design process and therefore the very nature of the architect’s work. Now there is more time for discussion and for additional cycles in the design process,’ says Ivarsson.
According to the students’ teachers, the decrease in the time required to produce a drawing has had another effect as well: the students do not need to put the same effort into planning a drawing as they used to. In the past, they had to do a lot of preparatory paper and pencil work to for example choose the right perspective.
Contact: Jonas Ivarsson
jonas.ivarsson@ped.gu.se
46-031-786-2473
University of Gothenburg
New ‘FeTRAM’ is promising computer memory technology
September 27, 2011
Researchers are developing a new type of computer memory that could be faster than the existing commercial memory and use far less power than flash memory devices.
The technology combines silicon nanowires with a “ferroelectric” polymer, a material that switches polarity when electric fields are applied, making possible a new type of ferroelectric transistor.
“It’s in a very nascent stage,” said doctoral student Saptarshi Das, who is working with Joerg Appenzeller, a professor of electrical and computer engineering and scientific director of nanoelectronics at Purdue’s Birck Nanotechnology Center.
The ferroelectric transistor’s changing polarity is read as 0 or 1, an operation needed for digital circuits to store information in binary code consisting of sequences of ones and zeroes. The new technology is called FeTRAM, for ferroelectric transistor random access memory.
“We’ve developed the theory and done the experiment and also showed how it works in a circuit,” he said. Findings are detailed in a research paper that appeared this month in Nano Letters, published by the American Chemical Society.
The FeTRAM technology has nonvolatile storage, meaning it stays in memory after the computer is turned off. The devices have the potential to use 99 percent less energy than flash memory, a non-volatile computer storage chip and the predominant form of memory in the commercial market.
“However, our present device consumes more power because it is still not properly scaled,” Das said. “For future generations of FeTRAM technologies one of the main objectives will be to reduce the power dissipation. They might also be much faster than another form of computer memory called SRAM.”
The FeTRAM technology fulfills the three basic functions of computer memory: to write information, read the information and hold it for a long period of time.
“You want to hold memory as long as possible, 10 to 20 years, and you should be able to read and write as many times as possible,” Das said. “It should also be low power to keep your laptop from getting too hot. And it needs to scale, meaning you can pack many devices into a very small area. The use of silicon nanowires along with this ferroelectric polymer has been motivated by these requirements.”
The new technology also is compatible with industry manufacturing processes for complementary metal oxide semiconductors, or CMOS, used to produce computer chips. It has the potential to replace conventional memory systems.
A patent application has been filed for the concept.
The FeTRAMs are similar to state-of-the-art ferroelectric random access memories, FeRAMs, which are in commercial use but represent a relatively small part of the overall semiconductor market. Both use ferroelectric material to store information in a nonvolatile fashion, but unlike FeRAMS, the new technology allows for nondestructive readout, meaning information can be read without losing it.
This nondestructive readout is possible by storing information using a ferroelectric transistor instead of a capacitor, which is used in conventional FeRAMs.
This work was supported by the Nanotechnology Research Initiative (NRI) through Purdue’s Network for Computational Nanotechnology (NCN), which is supported by National Science Foundation.
Writer:
Emil Venere
765-494-4709
venere@purdjue.edu
Sources:
Saptarshi Das
sdas@purdue.edu
Joerg Appenzeller
765-494-1076
appenzeller@purdue.edu
Related websites:
Joerg Appenzeller
http://www.purdue.edu/discoverypark/nanotechnology/membership/Appenzeller/index.html
Saptarshi Das
http://web.ics.purdue.edu/~sdas/research.html
Birck Nanotechnology Center
http://www.purdue.edu/discoverypark/nanotechnology/
Network for Computational Nanotechnology http://www.rcac.purdue.edu/projects/ncn.cfm
Note to Journalists:
An electronic copy of the research paper is available from:
Emil Venere
765-494-4709
venere@purdue.edu
A publication-quality image is available at http://news.uns.purdue.edu/images/2011/appenzeller-memory.jpg
Abstract on the research in this release can be found at: http://www.purdue.edu/newsroom/research/2011/110926AppenzellerMemory.html
Purdue University
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New ‘smart window’ system with unprecedented performance
September 21, 2011
A new “smart” window system has the unprecedented ability to inexpensively change from summer to winter modes, darkening to save air conditioning costs on scorching days and returning to crystal clarity in the winter to capture free heat from the sun, scientists are reporting. Their study appears in the journal ACS Nano.
Ho Sun Lim, Jeong Ho Cho, Jooyong Kim and Chang Hwan Lee point out that the drive for energy conservation has fostered efforts to develop new types of window glass for everything from skylights and windows in houses to conference room walls in offices. “Smart” windows that reflect sunlight away from buildings in summer and switch back to full transparency in winter already are available. But they have many drawbacks, including high cost, rapid deterioration in performance, and manufacturing processes that involve potentially toxic substances. So, the researchers set out to develop a smart window that overcomes these drawbacks.
They discovered that using a polymer, so-called “counterions” and a solvent such as methanol was an inexpensive and less harsh way to make a stable, robust smart window. It has the added advantage of being extremely tunable – quickly and easily switching from 100% opaque to almost completely clear in seconds. “To our knowledge, such extreme optical switching behavior is unprecedented among established smart windows,” the authors state. “This type of light control system may provide a new option for saving on heating, cooling and lighting costs through managing the light transmitted into the interior of a house.”
Contact: Michael Bernstein
m_bernstein@acs.org
202-872-6042
American Chemical Society
Proton-based transistor could let machines communicate with living things
September 20, 2011
Human devices, from light bulbs to iPods, send information using electrons. Human bodies and all other living things, on the other hand, send signals and perform work using ions or protons.
Materials scientists at the University of Washington have built a novel transistor that uses protons, creating a key piece for devices that can communicate directly with living things. The study is published online this week in the interdisciplinary journal Nature Communications.
Devices that connect with the human body’s processes are being explored for biological sensing or for prosthetics, but they typically communicate using electrons, which are negatively charged particles, rather than protons, which are positively charged hydrogen atoms, or ions, which are atoms with positive or negative charge.
“So there’s always this issue, a challenge, at the interface – how does an electronic signal translate into an ionic signal, or vice versa?” said lead author Marco Rolandi, a UW assistant professor of materials science and engineering. “We found a biomaterial that is very good at conducting protons, and allows the potential to interface with living systems.”
In the body, protons activate “on” and “off” switches and are key players in biological energy transfer. Ions open and close channels in the cell membrane to pump things in and out of the cell. Animals including humans use ions to flex their muscles and transmit brain signals. A machine that was compatible with a living system in this way could, in the short term, monitor such processes. Someday it could generate proton currents to control certain functions directly.
A first step toward this type of control is a transistor that can send pulses of proton current. The prototype device is a field-effect transistor, a basic type of transistor that includes a gate, a drain and a source terminal for the current. The UW prototype is the first such device to use protons. It measures about 5 microns wide, roughly a twentieth the width of a human hair.
“In our device large bioinspired molecules can move protons, and a proton current can be switched on and off, in a way that’s completely analogous to an electronic current in any other field effect transistor,” Rolandi said.
The device uses a modified form of the compound chitosan originally extracted from squid pen, a structure that survives from when squids had shells. The material is compatible with living things, is easily manufactured, and can be recycled from crab shells and squid pen discarded by the food industry.
First author Chao Zhong, a UW postdoctoral researcher, and second author Yingxin Deng, a UW graduate student, discovered that this form of chitosan works remarkably well at moving protons. The chitosan absorbs water and forms many hydrogen bonds; protons are then able to hop from one hydrogen bond to the next.
Computer models of charge transport developed by co-authors M.P. Anantram, a UW professor of electrical engineering, and Anita Fadavi Roudsari at Canada’s University of Waterloo, were a good match for the experimental results.
“So we now have a protonic parallel to electronic circuitry that we actually start to understand rather well,” Rolandi said.
Applications in the next decade or so, Rolandi said, would likely be for direct sensing of cells in a laboratory. The current prototype has a silicon base and could not be used in a human body. Longer term, however, a biocompatible version could be implanted directly in living things to monitor, or even control, certain biological processes directly.
The other co-author is UW materials science and engineering graduate student Adnan Kapetanovic. The research was funded by the University of Washington, a 3M Untenured Faculty Grant, a National Cancer Institute fellowship and the UW’s Center for Nanotechnology, which is funded by the National Science Foundation.
For more information, contact Rolandi at 206-221-0309 or rolandi@uw.edu.
Contact: Molly McElroy
mollywmc@uw.edu
206-543-2580
University of Washington
Robots are coming to aircraft assembly
September 19, 2011
The developers are presenting their new manufacturing approach at the Composites Europe trade fair in Stuttgart in Hall 4, Booth D03. One of this future assembly line’s first elements can also be seen there: a versatile component gripper made of lightweight CFRP (carbon fiber reinforced plastic). Aircraft parts are simply enormous. Individual fuselage segments alone can measure ten meters or more. But they need to be fitted together with the utmost precision. The maximum deviation from plan that aircraft manufacturers can tolerate is 0.2 millimeters – on components that weigh several metric tons. To position the giant parts accurately, manufacturers rely on massive production facilities known as assembly cells. These are huge gantries that move along the fuselage like container cranes on steel rails and massive concrete foundations, for instance bolting aluminum parts together. It takes a lot of money and effort to build this kind of assembly cell – and they need to be built from scratch for each new kind of aircraft, which pushes their production and construction costs even higher.
This state of affairs calls for automation concepts and facilities to make aircraft assembly – and in particular high-precision drilling, milling and adhesive bonding – simpler, more flexible and more economical in the future. And that is exactly what developers in the Fraunhofer Project Group Joining and Assembly FFM at the Fraunhofer Institute for Manufacturing Technology and Advanced Materials IFAM, Bremen, are working on at the research center CFK Nord in Stade. Theirs is a totally new assembly philosophy: Aircraft will in future be machined – and their parts increasingly bonded together – by a host of small industrial robots, much as we see in today’s automotive sector. Dr. Dirk Niermann, head of the Fraunhofer FFM, and his team of developers have come up with a design for a suitable facility that would replace the common assembly cell: They envision fuselage segments, tail fin and wings sitting atop a kind of rolling assembly line and being carried past one-armed robots, akin to automotive production methods. These robots then work at various points on the parts in succession to bond, drill and mill them as they pass. Of course, a facility of this kind would still need to be tailored to each new aircraft type, but the installation costs incurred would be significantly lower.
At the Composites Europe 2011 trade fair from September 27 to 29 (Hall 4, Booth D03), the scientists from Stade will be presenting the first key element of their new assembly line: a gripper that can deal flexibly with various geometries of aircraft component. “Aircraft are made up of shells of varying curvatures, and a gripper system has to be able to adjust accordingly,” says Niermann. This is done using configurable arrays of suction pads that sit on robust joints. The suction pads are mounted on a framework structure made of carbon fiber reinforced plastic that is both sturdy and considerably lighter than metal. Thanks to its low mass, industrial robots can position the gripper and the component with exceptional precision.
The gripper concept might seem only too simple, but in fact handling the components is a real challenge. Once they are put together, the dimensions of these large aircraft parts can deviate from plan by up to several millimeters as a consequence of their being fitted to the fuselage. Up to now, the fitting of these components into the fuselage has been painstakingly done by experienced technicians working on the assembly cell. The parts are sometimes even compressed or bent slightly in order not to breach the overall 0.2 millimeter tolerance. In future, it will be up to the robots and the gripper to achieve this. “That’s why we’re developing a high-precision recognition system to measure the components exactly during assembly,” says Niermann. This is combined with powerful software that takes fractions of a second to calculate the precise position in which the robot has to hold the workpiece to make everything fit together perfectly. However, there is one more challenge: Aluminum, the classic aircraft material, is increasingly being replaced by CFRP. But, unlike aluminum sheeting, CRFP components are unyielding during assembly, so they sometimes need to be assembled under tension. While technicians have developed a feel for how much tension is permissible, which allows them to assemble these parts manually, robots don’t know how to do this yet. Nonetheless, Niermann and his colleagues are certain that they will have an initial demonstration facility up and running around three years from now. The gripper can already be seen at Composites Europe, and the Fraunhofer Project Group Joining and Assembly FFM is also presenting its entire robotic aircraft assembly concept there.
Contact: Sarah Ernst
sarah.ernst@ifam.fraunhofer.de
49-414-178-707-281
Fraunhofer-Gesellschaft
Lasers could be used to detect roadside bombs
September 16, 2011
A research team at Michigan State University has developed a laser that could detect roadside bombs – the deadliest enemy weapon encountered in Iraq and Afghanistan.
The laser, which has comparable output to a simple presentation pointer, potentially has the sensitivity and selectivity to canvas large areas and detect improvised explosive devices – weapons that account for around 60 percent of coalition soldiers’ deaths. Marcos Dantus, chemistry professor and founder of BioPhotonic Solutions, led the team and has published the results in the current issue of Applied Physics Letters.
The detection of IEDs in the field is extremely important and challenging because the environment introduces a large number of chemical compounds that mask the select few molecules that one is trying to detect, Dantus said.
“Having molecular structure sensitivity is critical for identifying explosives and avoiding unnecessary evacuation of buildings and closing roads due to false alarms,” he said
Since IEDs can be found in populated areas, the methods to detect these weapons must be nondestructive. They also must be able to distinguish explosives from vast arrays of similar compounds that can be found in urban environments. Dantus’ latest laser can make these distinctions even for quantities as small as a fraction of a billionth of a gram.
The laser beam combines short pulses that kick the molecules and make them vibrate, as well as long pulses that are used to “listen” and identify the different “chords.” The chords include different vibrational frequencies that uniquely identify every molecule, much like a fingerprint. The high-sensitivity laser can work in tandem with cameras and allows users to scan questionable areas from a safe distance.
“The laser and the method we’ve developed were originally intended for microscopes, but we were able to adapt and broaden its use to demonstrate its effectiveness for standoff detection of explosives,” said Dantus, who hopes to net additional funding to take this laser from the lab and into the field.
This research is funded in part by the Department of Homeland Security. BioPhotonic Solutions is a high-tech company Dantus launched in 2003 to commercialize technology invented in a spinoff from his research group at MSU.
Michigan State University has been working to advance the common good in uncommon ways for more than 150 years. One of the top research universities in the world, MSU focuses its vast resources on creating solutions to some of the world’s most pressing challenges, while providing life-changing opportunities to a diverse and inclusive academic community through more than 200 programs of study in 17 degree-granting colleges.
Contact: Layne Cameron
layne.cameron@ur.msu.edu
517-353-8819
Michigan State University
Quantum behavior with a flash
September 16, 2011
Just as a camera flash illuminates unseen objects hidden in darkness, a sequence of laser pulses can be used to study the elusive quantum behavior of a large “macroscopic” object. This method provides a novel tool of unprecedented performance for current experiments that push the boundaries of the quantum world to larger and larger scales. A collaboration of scientists led by researchers from the Vienna Center for Quantum Science and Technology (VCQ) at the University of Vienna report this new scheme in the forthcoming issue of PNAS.
One of the most fascinating and still open questions in physics is how far quantum phenomena extend into our everyday world. To answer that, experiments need to peer into the quantum world at a completely new scale of mass and size. This is a bumpy road: it becomes increasingly difficult to detect the genuine quantum features as mass and size are increased.
Overcoming the “blur”
Publishing under the title “Pulsed quantum optomechanics” the research team proposes a method that uses flashes of light to observe quantum features of large objects with unprecedented resolution. The main idea is based on the fact that quantum objects, in contrast to classical objects, behave differently when they are being watched. “In current approaches, objects are constantly monitored and the possible quantum features are being washed out. This is in many ways analogous to the blurring of a photograph of a fast moving object”, says Michael R. Vanner, lead author of the paper and member of the Vienna Doctoral School Complex Quantum Systems (CoQuS). “Loosely speaking, the flashes freeze the motion and create a sharp image of the quantum behavior.”
How macroscopic can “quantum” be?
With this new tool, experiments will be able to peer into the quantum world at a completely new scale of mass and size. In particular, the scheme can be directly applied to the ongoing experiments that attempt to prepare quantum phenomena in micro-mechanical resonators, i.e. mechanically vibrating massive objects. “By analyzing the dynamics of such behavior, pulsed quantum optomechanics provides a path for investigating whether macroscopic mechanical objects can be used in future quantum technologies. It will also help shed light on nature’s apparent division between the quantum and the classical worlds.”
International cooperation
This work has been undertaken as a joint effort by researchers of the Vienna Center for Quantum Science and Technology (VCQ) of the University of Vienna, the Imperial College London, the Institute for Quantum Optics and Quantum Information (IQOQI), the Albert-Einstein Institute of the University of Hannover and the University of Queensland. It was supported by: Australian Research Council, Engineering and Physical Sciences Research Council, European Research Council, European Commission, Foundational Questions Institute, Austrian Science Fund and Austrian Academy of Sciences.
Publication
Pulsed quantum optomechanics. M. R. Vanner, I. Pikovski, G. D. Cole, M. S. Kim, Č. Brukner, K. Hammerer, G. J. Milburn, and M. Aspelmeyer. In: Proceedings of the National Academy of Sciences USA (PNAS). DOI: 10.1073/pnas.1105098108
Contact: Michael R. Vanner
michael.vanner@univie.ac.at
43-142-777-2533
University of Vienna
Personalized 3-D avatars for real life
September 15, 2011
An avatar is really no more than a graphical representation, generally human, which is associated with a user for identification purposes. Avatars can be either photographs or art drawings, and certain technologies enable their use in three dimensions.
Until now, 3D avatars were mainly used as fun objects for diversion and entertainment purposes of the end user. However, the Media Unit at Tecnalia has developed a “Personalised 3D avatars” technology, the aim of which is to facilitate the building of low-cost 3D avatars.
This 3D avatar is used as a responsible interface to give advice to users, motivating them and guiding them while interacting with the computer. This new technology enables the provision of a novel solution in the use of these avatars in fields such as plastic surgery and Alzheimer’s disease, and with which, based on high-quality 3D laser scanners and 2D photographs, Personalised 3D avatars are achieved.
In the case of plastic surgery, and using MODELVIR (Virtual Modelling) within the field of plastic and repair surgery, the surgeon is provided with an easy-to-use tool which enables graphically representing the current state of the patient, as well as a novel, three-dimensional representation of his or her external aspect after the operation. In this way the patient has a better idea of what the plastic surgeon can achieve, without creating illusions or raising false hopes that could give rise to subsequent disappointment.
Then there is ALZHERAPY, a technical project linked to the fight against Alzheimer’s disease and that aims to provide rapid diagnosis for this pathology. Thus, the rate of advance of the disease slows on carrying out cognitive exercises. It has the added possibility of undertaking the daily monitoring and evaluation of the patient in a personalised manner, using an avatar that represents a person with a close likeness to him or her, and without having to leave the house. It even provides the possibility of enabling the patient to leave home without accompaniment (thus leading a normal pace of life) with total security, thanks to a device capable of detecting his or her position at any time.
Contact: Irati Kortabitarte
i.kortabitarte@elhuyar.com
34-943-363-040
Elhuyar Fundazioa
Newly published cyber security report identifies key research priorities
September 13, 2011
Newly published cyber security report identifies key research priorities for safeguarding the Internet of tomorrow
Outcome of CSIT’s Belfast 2011 Cyber Summit represents a global collective strategy for world’s leading research institutes
Developing self-learning, self aware cyber security technologies, protecting smart utility grids and enhancing the security of mobile networks are among the top research priorities needed to safeguard the internet of tomorrow, according to a report released today.
Published by the UK’s National Centre for Secure Information Technologies (CSIT), the report represents the outcome of discussions held during the inaugural World Cyber Security Technology Research Summit hosted by CSIT earlier this year.
The Belfast 2011 event attracted international cyber security experts from leading research institutes, government bodies and industry who gathered to discuss current cyber security threats, predict future threats and the necessary mitigation techniques, and to develop a collective strategy for next generation research.
The collective research strategy contained in the report identifies four research themes critical to the ongoing creation of cyber security defences:
- Adaptive cyber security technologies – research objectives in this area will include the development of self-learning cyber security technologies; self-awareness in cyber systems; the establishment of feedback in cyber systems to learn from cyber attacks.
- Protection of smart utility grids – research aims in this field will comprise: smart grid requirements gathering methodology; protection technologies for smart grid components; secure technologies for smart grid communications; smart grid and home area network integration that provides privacy and security of collected information; development of smart grid standards.
- Security of the mobile platform and applications – research in this space will target not only malicious applications but also mobile cyber security problems introduced by the configuration and use of mobile networks, including network availability, mobile web browsers and caller authentication.
- Multi-faceted approach to cyber security research – research will take into account social behavioural norms and societal desires in cyber space, cyber space policies, the impact of cyber and other legislation and the economics of cyber space and cyber security.
“Belfast 2011 brought together a diverse range of talent and knowledge in the cyber security field from which we have developed this strategy for next generation research,” says Prof John McCanny CSIT’s Principal Investigator.
“Our ambition is that this strategy will help to inform global cyber security research and act as a driver for cyber security roadmap definition over the coming year. We will hold future summits at which changes in cyber security will be discussed and the proposed collective research strategies will be reviewed and developed.”
Notes to editors
Copies of the World Cyber Security Technology Research Summit Report – Belfast 2011 – are available from www.csit.qub.ac.uk
About Belfast 2011
Participants at the inaugural World Cyber Security Technology Research Summit included representatives of the UK Home Office, US Department of Commerce, US Cyber Consequences Unit, Stanford University, Carnegie Mellon University, BAE Systems, Thales and IBM.
About CSIT
The Centre for Secure Information Technologies (CSIT) is an innovation and knowledge centre based at Queen’s University of Belfast’s, Institute of Electronics, Communications and Information Technology (ECIT). Funded by EPSRC, TSB, Invest NI and industry collaborators, the Centre brings together research specialists in complementary fields such as data encryption, network security systems, wireless enabled security systems and intelligent surveillance technology.
CSIT is developing innovative and novel technology in both information and people security applications and is focused on key grand challenges (1) Secure Hyperconnected Networks (Smart Grid Security, Cloud Security, Cyber Security), (2) Secure Transport Corridors (Bus, Train, Airport Security) and (3) Security and Trust in the Financial Sector (e-Crime, Capital Market Security).
CSIT’s member companies include: Altera, BAE Systems, Cisco, Q1Labs and Thales as well as government agencies with strong interests in this area. These include the Home Office, GCHQ, CESG, CPNI and DSTL.
Technologies being developed at CSIT include powerful computer processors that can detect and filter malware and cyber attacks within large networks in real-time, Physical Unclonable Functions that provide a lightweight and secure digital fingerprint for physical devices and an Intelligent Reasoning Algorithm that can take large volumes of multi-agent information from CCTV, RFID etc and rationalise and identify security events within transport networks.
For further information, please contact: Brian Arlow on +44 7860 289143
Contact: Brian Arlow
44-786-028-9143
Queen’s University Belfast
Graphene may open the gate to future terahertz technologies
September 12, 2011
Researchers from the University of Notre Dame in Indiana have harnessed another one of graphenes remarkable properties to better control a relatively untamed portion of the electromagnetic spectrum: the terahertz band.
Terahertz radiation offers tantalizing new opportunities in communications, medical imaging, and chemical detection. Straddling the transition between the highest energy radio waves and the lowest energy infrared light, terahertz waves are notoriously difficult to produce, detect, and modulate. Modulation, or varying the height of the terahertz waves, is particularly important because a modulated signal can carry information and is more versatile for applications such as chemical and biological sensing. Some of todays most promising terahertz technologies are based on small semiconductor transistor-like structures that are able to modulate a terahertz signal at room temperature, which is a significant advantage over earlier modulators that could only operate at extremely cold temperatures.
Unfortunately, these transistor-like devices rely on a thin layer of metal called a metal gate to tune the terahertz signal. This metal gate significantly reduces the signal strength and limits how much the signal can be modulated to a lackluster 30 percent. As reported in the AIPs journal Applied Physics Letters, by replacing the metal gate with a single layer of graphene, the researchers have predicted that the modulation range can be significantly expanded to be in excess of 90 percent. This modulation is controlled by applying a voltage between the graphene and semiconductor. Unlike the metal gate modulator, the graphene design barely diminished the output power of the terahertz energy. Made up of a one-atom-thick sheet of carbon atoms, graphene boasts a host of amazing properties: its remarkably strong, a superb thermal insulator, a conductor of electricity, and now a better means to modulate terahertz radiation.
Article: Unique prospects for graphene-based terahertz modulators is accepted for publication in Applied Physics Letters.
Authors: Berardi Sensale-Rodriguez (1), Tian Fang (1), Rusen Yan (1), Michelle M. Kelly (1), Debdeep Jena (1), Lei Liu (1), and Huili (Grace) Xing (1).
(1) Department of Electrical Engineering, University of Notre Dame
Contact: Charles E. Blue
cblue@aip.org
301-209-3091
American Institute of Physics