Imagine a hole so small that air can’t go through it, or a hole so small it can trap a single wavelength of light. Nanotech Security Corp., with the help of Simon Fraser University (SFU) researchers, is using this type of nanotechnology -- 1,500 times thinner than a human hair and first of its kind in the world -- to create unique anti-counterfeiting security features. The technology is first being applied to banknotes but it also has many more practical applications, such as authenticating legal documents, retail merchandise, concert tickets, stock certificates, visas, passports, and pharmaceuticals. SFU applied sciences grad Clint Landrock started the initial research into nanoholes under the guidance of SFU engineering science professor Bozena Kaminska. When the pair pitched their idea to Doug Blakeway, CEO and chairman of Nanotech, he was immediately intrigued by the technology’s potential. Landrock and Kaminska both continue their work as part of Nanotech’s scientific team. The company’s Nano-Optic Technology for Enhanced Security (NOtES) product stems from an idea originating in the purest form of nature – insects using colorful markings to identify themselves. How this works is microscopic gratings composed of nanostructures interact with light to produce the shimmering iridescence seen on the Costa Rican morpho butterfly. The nanostructures act to reflect and refract light waves to produce the morpho’s signature blue wings and absorb other unwanted light. The highly advanced wing structures are the result of many millennia of evolution, and only recently have Nanotech's scientists discovered how to reproduce these structures reliably. Banknotes contain several security features – some that you can plainly see and some that only machines can read – such as hologram strips, security threads woven into the paper, watermarks, color-shifting inks, raised type, and UV inks. According to Blakeway, Nanotech’s product -- which has attracted the attention of treasuries internationally -- is superior to holograms and can’t be duplicated.
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Imperial scientists are developing technology that could lead to ultrafast DNA sequencing tool within ten years. (Image Credit: Imperial College London)
Scientists from Imperial College London are developing technology that could ultimately sequence a person's genome in mere minutes, at a fraction of the cost of current commercial techniques. The researchers have patented an early prototype technology that they believe could lead to an ultrafast commercial DNA sequencing tool within ten years. The research suggests that scientists could eventually sequence an entire genome in a single lab procedure, whereas at present it can only be sequenced after being broken into pieces in a highly complex and time-consuming process. Fast and inexpensive genome sequencing could allow ordinary people to unlock the secrets of their own DNA, revealing their personal susceptibility to diseases such as Alzheimer's, diabetes and cancer. In the new study, the researchers demonstrated that it is possible to propel a DNA strand at high speed through a tiny 50 nanometre (nm) hole - or nanopore - cut in a silicon chip, using an electrical charge. As the strand emerges from the back of the chip, its coding sequence (bases A, C, T or G) is read by a 'tunnelling electrode junction'. This 2 nm gap between two wires supports an electrical current that interacts with the distinct electrical signal from each base code. A powerful computer can then interpret the base code's signal to construct the genome sequence, making it possible to combine all these well-documented techniques for the first time. Sequencing using nanopores has long been considered the next big development for DNA technology, thanks to its potential for high speed and high-capacity sequencing. However, designs for an accurate and fast reader have not been demonstrated until now.
IBM's new CMOS Integrated Silicon Nanophotonics chip technology integrates electrical and optical devices on the same piece of silicon, enabling computer chips to communicate using pulses of light (instead of electrical signals).(Image Credit: IBM )
IBM scientists have unveiled a new chip technology that integrates electrical and optical devices on the same piece of silicon, enabling computer chips to communicate using pulses of light (instead of electrical signals), resulting in smaller, faster and more power-efficient chips than is possible with conventional technologies. The new technology, calledCMOS Integrated Silicon Nanophotonics, is the result of a decade of development at IBM's global Research laboratories. The patented technology will change and improve the way computer chips communicate -- by integrating optical devices and functions directly onto a silicon chip, enabling over 10X improvement in integration density than is feasible with current manufacturing techniques. IBM anticipates that Silicon Nanophotonics will dramatically increase the speed and performance between chips, and further the company's ambitious Exascale computing program, which is aimed at developing a supercomputer that can perform one million trillion calculations -- or an Exaflop -- in a single second. An Exascale supercomputer will be approximately one thousand times faster than the fastest machine today.
“The development of the Silicon Nanophotonics technology brings the vision of on-chip optical interconnections much closer to reality,” said Dr. T.C. Chen, vice president, Science and Technology, IBM Research. “With optical communications embedded into the processor chips, the prospect of building power-efficient computer systems with performance at the Exaflop level is one step closer to reality.” In addition to combining electrical and optical devices on a single chip, the new IBM technology can be produced on the front-end of a standard CMOS manufacturing line and requires no new or special tooling. With this approach, silicon transistors can share the same silicon layer with silicon nanophotonics devices. To make this approach possible, IBM researchers have developed a suite of integrated ultra-compact active and passive silicon nanophotonics devices that are all scaled down to the diffraction limit – the smallest size that dielectric optics can afford.
(Image Credit: University of Nottingham)
Scientists at the University of Nottingham have made a major breakthrough that could help shape the future of nanotechnology, by demonstrating for the first time that 3-D molecular structures can be built on a surface. The discovery could prove a significant step forward towards the development of new nano devices such as cutting-edge optical and electronic technologies and even molecular computers. The team of chemists and physicists at Nottingham have shown that by introducing a ‘guest’ molecule they can build molecules upwards from a surface rather than just 2-D formations previously achieved. A natural biological process known as ‘self-assembly’ meant that once the scientists introduced other molecules on to a surface their host then spontaneously arranged them into a rational 3-D structure. Professor Neil Champness said: “It is the molecular equivalent of throwing a pile of bricks up into the air and then as they come down again they spontaneously build a house. “Until now this has only been achievable in 2-D, so to continue the analogy the molecular ‘bricks’ would only form a path or a patio but our breakthrough now means that we can start to build in the third dimension. It’s a significant step forward to nanotechnology.” Previously, scientists have employed a technique found in nature of using hydrogen bonds to hold DNA together to build two-dimensional molecular structure.
The new process involved introducing a guest molecule -- in this case a ‘buckyball’ or C60 -- on to a surface patterned by an array of tetracarboxylic acid molecules. The spherical shape of the buckyballs means they sit above the surface of the molecule and encourage other molecules to form around them. It offers scientists a completely new and controlled way of building up additional layers on the surface of the molecule. The work is the culmination of four years’ of research led by Professors Champness and Beton from the School of Chemistry and the School of Physics and Astronomy, which has been funded with a total of £3.5 million from the Engineering and Physical Sciences Research Council.
Twisting spires are one of the 3D shapes researchers at the University of Michigan were able to develop using a new manufacturing process.(Image Credit: University of Michigan, A. John Hart )
Twisting spires, concentric rings, and gracefully bending petals are a few of the new three-dimensional shapes that University of Michigan engineers can make from carbon nanotubes using a new manufacturing process. The process is called “capillary forming,” and it takes advantage of capillary action, the phenomenon at work when liquids seem to defy gravity and spontaneously travel up a drinking straw. The new miniature shapes have the potential to harness the exceptional mechanical, thermal, electrical, and chemical properties of carbon nanotubes in a scalable fashion, said A. John Hart, an assistant professor in the Department of Mechanical Engineering and in the School of Art & Design. The 3D nanotube structures could enable countless new materials and microdevices, including probes that can interface with individual cells, novel microfluidic devices, and lightweight materials for aircraft and spacecraft.
“It’s easy to make carbon nanotubes straight and vertical like buildings,” Hart said. “It hasn’t been possible to make them into more complex shapes. Assembling nanostructures into three-dimensional shapes is one of the major goals of nanotechnology and nanomanufacturing. The method of capillary forming could be applied to many types of nanotubes and nanowires, and its scalability is very attractive for manufacturing.” Hart’s method starts by patterning a thin metal film on a silicon wafer. This film is the iron catalyst that facilitates the growth of vertical carbon nanotube “forests” in patterned shapes. It’s a sort of template. Rather than pattern the catalyst into uniform shapes such as circles and squares, Hart's team patterns a variety of unique shapes such as hollow circles, half circles, and circles with smaller ones cut from their centers. The shapes are arranged in different orientations and groupings, creating different templates for later forming the 3D structures using capillary action.
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Professor Andre Geim and Professor Konstantin Novoselov of the University of Manchester have been awarded the highest accolade in the scientific world for their pioneering work with the world’s thinnest material. (Image Credit: University of Manchester )
A thin flake of ordinary carbon, just one atom thick, lies behind this year’s Nobel Prize in Physics. Andre Geim and Konstantin Novoselov have shown that carbon in such a flat form has exceptional properties that originate from the remarkable world of quantum physics. Graphene is a form of carbon. As a material it is completely new – not only the thinnest ever but also the strongest. As a conductor of electricity it performs as well as copper. As a conductor of heat it outperforms all other known materials. It is almost completely transparent, yet so dense that not even helium, the smallest gas atom, can pass through it. Carbon, the basis of all known life on earth, has surprised us once again. Geim and Novoselov extracted the graphene from a piece of graphite such as is found in ordinary pencils. Using regular adhesive tape they managed to obtain a flake of carbon with a thickness of just one atom. This at a time when many believed it was impossible for such thin crystalline materials to be stable.
However, with graphene, physicists can now study a new class of two-dimensional materials with unique properties. Graphene makes experiments possible that give new twists to the phenomena in quantum physics. Also a vast variety of practical applications now appear possible including the creation of new materials and the manufacture of innovative electronics. Graphene transistors are predicted to be substantially faster than today’s silicon transistors and result in more efficient computers. Since it is practically transparent and a good conductor, graphene is suitable for producing transparent touch screens, light panels, and maybe even solar cells. When mixed into plastics, graphene can turn them into conductors of electricity while making them more heat resistant and mechanically robust. This resilience can be utilised in new super strong materials, which are also thin, elastic and lightweight. In the future, satellites, airplanes, and cars could be manufactured out of the new composite materials.
This year’s Laureates have been working together for a long time. Konstantin Novoselov, 36, first worked with Andre Geim, 51, as a PhD-student in the Netherlands. He subsequently followed Geim to the United Kingdom. Both of them originally studied and began their careers as physicists in Russia. Now they are both professors at the University of Manchester in the United Kingdom.
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(Image Credit: University of Twente )
Earlier musical instruments with these minimal dimensions only produced tones that are inaudible to humans. But thanks to ingenious construction techniques, students from the University of Twente in the Netherlands have succeeded in producing scales that are audible when amplified. To do so, they made use of the possibilities offered by micromechanics: the construction of moving structures with dimensions measured in micrometres (a micrometre is a thousandth of a millimetre). These miniscule devices can be built thanks to the ultra-clean conditions in a 'clean room', and the advanced etching techniques that are possible there. "You can see comparable technology used in the Wii games computer for detecting movement, or in sensors for airbags", says PhD student Johan Engelen, who devised and led the student project. The tiny musical instrument is made up of springs that are only a tenth of the thickness of a human hair, and vary in length from a half to a whole millimetre. A mass of a few dozen micrograms is hung from these springs. The mass is set in motion by so-called 'comb drives': miniature combs that fit together precisely and shift in relation to each other, so 'plucking' the springs and creating sounds. The mass vibrates with a maximum deflection of just a few micrometres. This minimal movement can be accurately measured, and produces a tone. Each tone has its own mass spring system, and six tones fit on a microchip. By combining a number of chips, a wider range of tones can be achieved. "The tuning process turned out to be the greatest challenge", says Engelen. "We can learn a lot from this project for the construction of other moving structures. Above all, this is a great project for introducing students to micromechanics and clean room techniques." The video below shows a recent concert using the technology.
A visualization of the nanoscale interaction between a semiconducting substrate (below) and graphene. (Credit: Joe Lyding, U. Illinois)
New findings from the laboratory of Beckman Institute for Advanced Science and Technology (University of Illinois at Urbana-Champaign) researcher Joe Lyding are providing valuable insight into graphene, a single two-dimensional layer of graphite with numerous electronic and mechanical properties that make it attractive for use in electronics. Lyding, who heads the Nanoelectronics and Nanomaterials group at Beckman, and his lab report using a dry deposition method they developed to deposit pieces of graphene on semiconducting substrates and on the electronic character of graphene at room temperature they observed using the method. The researchers wrote this of graphene’s potential, especially as compared to its elemental cousin, carbon nanotubes, for use in electronics and other applications: “It exhibits the quantum hall effect, even at room temperature, and its optical transparency is directly related to the fine structure constant. Graphene is more and more being thought of as a fairly strong and elastic membrane (with an associated potential as a material for NEMS applications). Unlike carbon nanotubes, graphene can be patterned using standard e-beam lithographic techniques, making it an attractive prospect for use in semiconductor devices.” To reach that goal, issues associated with graphene must be overcome, and the research gives insight into a much-needed step in that direction: understanding substrate-graphene interactions toward integration into future nanoelectronic devices. The project investigated the electronic character of the underlying substrate of graphene at room temperature and reports on “an apparent electronic semitransparency at high bias of the nanometer-sized monolayer graphene pieces observed using an ultrahigh vacuum scanning tunneling microscope (UHV-STM) and corroborated via first-principles studies.” This semitransparency was made manifest by observation of the substrate atomic structure through the graphene.
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A scanning electron microscope image of the silver nanowires in which the cotton is dipped during the process of constructing a filter. The large fibers are cotton. (Credit: Stanford University)
By dipping plain cotton cloth in a high-tech broth full of silver nanowires and carbon nanotubes, Stanford University researchers have developed a new high-speed, low-cost filter that could easily be implemented to purify water in the developing world. Instead of physically trapping bacteria as most existing filters do, the new filter lets them flow on through with the water. But by the time the pathogens have passed through, they have also passed on, because the device kills them with an electrical field that runs through the highly conductive "nano-coated" cotton. In lab tests, over 98 percent of Escherichia coli bacteria that were exposed to 20 volts of electricity in the filter for several seconds were killed. Multiple layers of fabric were used to make the filter 2.5 inches thick. "This really provides a new water treatment method to kill pathogens," said Yi Cui, an associate professor of materials science and engineering. "It can easily be used in remote areas where people don't have access to chemical treatments such as chlorine." Cholera, typhoid and hepatitis are among the waterborne diseases that are a continuing problem in the developing world. Cui said the new filter could be used in water purification systems from cities to small villages.
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University of Pennsylvania researchers developed a carbon-based, nanoscale platform to electrically detect single DNA molecules. Electric fields push tiny DNA strands through atomically-thin graphene nanopores that ultimately may sequence DNA bases by their unique electrical signature. (Credit: University of Pennsylvania; Art: Robert Johnson)
Researchers at the University of Pennsylvania have developed a new, carbon-based nanoscale platform to electrically detect single DNA molecules. Using electric fields, the tiny DNA strands are pushed through nanoscale-sized, atomically thin pores in a graphene nanopore platform that ultimately may be important for fast electronic sequencing of the four chemical bases of DNA based on their unique electrical signature. The pores, burned into graphene membranes using electron beam technology, provide Penn physicists with electronic measurements of the translocation of DNA. “We were motivated to exploit the unique properties of graphene — a two-dimensional sheet of carbon atoms — in order to develop a new nanopore electrical platform that could exhibit high resolution,” said Marija Drndi, associate professor in the Department of Physics and Astronomy in Penn’s School of Arts and Sciences. “High resolution of graphene nanopore devices is expected because the thickness of the graphene sheet is smaller than the distance between two DNA bases. Graphene has previously been used for other electrical and mechanical devices, but up until now it has not been used for DNA translocation." The research team had made graphene nanopores in a study completed two years ago and in this study put the pores to work. Graphene nanopore devices developed by the Penn team work in a simple manner. The pore divides two chambers of electrolyte solution and researchers apply voltage, which drives ions through the pores. Ion transport is measured as a current flowing from the voltage source. DNA molecules, inserted into the electrolyte, can be driven single file through such nanopores.
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