Researchers at Rice University (USA) have developed a micron-scale spatial light modulator (SLM) similar to those currently used in sensing and imaging devices, but with the potential to run several orders of magnitude faster. Their ‘antenna on a chip’ operates in 3D ‘free space’ instead of the two-dimensional space of conventional semiconductor devices.
A device that looks like a tiny washboard may clean the clocks of current commercial products used to manipulate infrared light.
New research by the Rice University lab of Qianfan Xu has produced a micron-scale spatial light modulator (SLM) like those used in sensing and imaging devices, but with the potential to run orders of magnitude faster. Unlike other devices in two-dimensional semiconducting chips, the Rice chips work in three-dimensional “free space.”
In current optical computing devices, light is confined to two-dimensional circuitry and travels in waveguides from point to point. According to the researchers, 2D systems ignore the massive multiplexing capability of optical systems arising from the fact that multiple light beams can propagate in the same space without affecting each other. [via]
“Antenna on Chip” Manipulates Light at Warp Speed - [Link]
A team at Rice University (USA) has devised a method for making nearly transparent films of conductive carbon nanotubes, a goal sought by researchers around the world. They found that dipping slides into a solution of pure nanotubes in chlorosulphonic acid (CSA) left them with an even coating that, after further processing, had none of the disadvantages seen with other methods. According to the researchers, the method is scalable to high-throughput industrial processes such as slot, slide and roll coating. The films, which could potentially be used for touchscreens, remained electrically stable after more than three months, according to the team.
Nearly Transparent Conductive Films - [Link]
Data storage is becoming increasingly important as digital information doubles in volume roughly every two years. By the end of 2012 the volume will have grown 48% compared to 2011, the International Data Corporation (IDC) predicts.
Bioengineers have been jealously eyeballing nature’s information storage medium DNA for its efficiency and robustness.
Information stored in DNA can survive for a hundreds of thousand of years. Unlike data centers, DNA doesn’t need climate-control because it can withstand just about any environmental circumstance. As long as the data isn’t accessed there is no energy cost. And above all it has an extremely high storage density.
Now Harvard researchers report a major breakthrough. They have successfully encoded the contents of a book in DNA, copied it 70 billion times and fitted it on a space the size of a thumbnail. [via]
All data humanity creates in a year stored on 4 grams of DNA - [Link]
Physicists at the University of Utah (USA) have invented a new ‘spintronic’ organic light-emitting diode (OLED) with the potential to be brighter, cheaper and more environmentally friendly than existing LEDs. They made a prototype of what is called a spin-polarized organic LED, or spin OLED, that emits orange light. In time the new technology could be extended to emit red and blue light, and possibly even white light. It may take a while for the new LEDs to go commercial, because they only operate at cold temperatures (-33 °C), so more work is needed to develop practical devices.
The new OLED is based on spintronic devices, which utilise the spins of electrons in a semiconductor material to store or gate data. The researchers discovered that with key advances in the organic semiconductor material, spin valve devices could also be made to emit light. The first advance is to use deuterium (‘heavy hydrogen’) instead of normal hydrogen in the organic layer, which increases efficiency. The second advance is to deposit an extremely thin layer of lithium fluoride on the cobalt electrode, which allows electrons to be injected on one side of the spin valve while holes are injected on the other side. This makes the spin valve bipolar, unlike older spin valves which only allow hole injection. [via]
New OLED Spins Brighter - [Link]
There’s a 5-in-10 million chance that this is a fluke. That was enough for physicists to declare that the Higgs boson – the world’s most-wanted particle – has been discovered. Rapturous applause, whistles and cheers filled the auditorium at CERN, near Geneva, Switzerland.
Almost 50 years after its existence was first predicted, the breakthrough means that the standard model of particle physics, which explains all known particles and the forces that act upon them, is now complete.
A Higgs boson with a mass of around 125 to 126 gigaelectronvolts (GeV) was seen separately by the twin CMS and ATLAS detectors at the Large Hadron Collider, each with a confidence level of 5 sigma, or standard deviations, the heads of the experiments announced today at CERN.
Even by particle physicists’ strict standards, that’s statistically significant enough to count as a particle discovery.
“I think we have it,” said Rolf Heuer, director general of CERN, as he concluded a hotly-anticipated seminar, which began today at 9am local time.
Scientists Believe They Have Discovered the Higgs Boson! - [Link]
Bill shows the world’s smallest atomic clock and then describes how the first one made in the 1950s worked. He describes in detail the use of cesium vapor to create a feedback or control loop to control a quartz oscillator. He highlights the importance of atomic team by describing briefly how a GPS receiver uses four satellites to find its position. You can learn more about atomic clocks and the GPS system in the EngineerGuy team’s new book Eight Amazing Engineering Stories http://www.engineerguy.com/elements
How an atomic clock works, and its use in the global positioning system (GPS) - [Link]
Power plants and many industrial processes produce heat as a byproduct, as much as up to 50% of the initial energy input may be released as heat. What if we could store this waste heat for later use?
The most common form of thermal storage is in insulated water tanks, but water can only retain heat for a short period of time as it cools off gradually. Zeolite is a mineral that can store up to four times more heat than water can, but, unlike water, zeolite retains all of the heat for an unlimited period of time. Although these unique properties of zeolite are well known, it is only now that scientists of the German Fraunhofer Institute have succeeded in using the mineral to build a working thermal storage system. [via]
Store Thermal Energy Forever - [Link]
Researchers at the University of Basel in Switzerland say they have developed a new approach to producing environmentally sustainable photovoltaic devices. The research team developed a new method for producing dye substances and attaching them to the surface of titanium dioxide nanoparticles. With this they demonstrated that simple dye compounds based on zinc, a readily available metal, can be used.
Dye-sensitized solar cells (DSCs) consist of titanium dioxide, a semiconductor material coated with a colored dye. The dye absorbs sunlight and injects electrons into the titanium dioxide, which ultimately results in a photovoltaic current. Conventional DSCs use ruthenium dyes, but ruthenium is very rare and expensive. The research team showed that dyes made with abundant and relatively inexpensive copper are effective in DSCs, and that low-cost zinc compounds can also be used. Although the new devices are not yet especially efficient, the finding opens the way to new generations of DSCs with previously ignored dye types. [via]
Dye-sensitized Solar Cells based on Zinc Compounds - [Link]
Nanotransistors just got a lot more nano. A new chip construction process cooked up by Applied Materials in Santa Clara creates transistors so small they can be measured in smatterings of atoms.
The company can now coax a few dozen of the little guys to assemble themselves into a base layer that helps control the flow of electricity on computer chips. The biggest development is the manufacturing process: Applied Materials devised a way to keep several interconnected manufacturing machines in a near-total vacuum—at this level, a single stray nanoparticle can ruin everything.
The other part of the breakthrough is making this base from hafnium (used also in nuclear control rods) instead of the standard silicon oxynitride, which is terrible at holding back electrons on a supersmall scale. (Gordon Moore himself has called this technique the biggest advancement in the field in 40 years—and it is likely to keep processors advancing on pace with his eponymous law for the foreseeable future.)
Applied Materials’ system means transistors can be about 22 nanometers wide, as opposed to the current standard of about 45 nanometers, resulting in smaller, cheaper computing devices.
CA Lab Creates the World’s Smallest Transistors - [Link]
Researchers at the University of Leeds have used a type of bacterium which ‘eats’ iron to create a surface of magnets, similar to those found in traditional hard drives, and wiring. As the bacterium ingests the iron it creates tiny magnets within itself. The team has also begun to understand how the proteins inside these bacteria collect, shape and position these “nanomagnets” inside their cells and can now replicate this behavior outside the bacteria. Using this knowledge the team hopes to develop a ‘bottom-up’ approach for creating cheaper, more environmentally-friendly electronics of the future.
The magnetic array was created using a protein which creates perfect nanocrystals of magnetite inside the bacterium Magnetospirilllum magneticum. In a process akin to potato-printing on a much smaller scale, this protein is attached to a gold surface in a checkerboard pattern and placed in a solution containing iron. At a temperature of 80°C, similarly-sized crystals of magnetite form on the sections of the surface covered by the protein. The researchers are now working to reduce the size of these islands of magnets, in order to make arrays of single nanomagnets. They also plan to vary the magnetic materials that this protein can control. These next steps would allow each of these nanomagnets to hold one bit of information allowing the construction of better hard drives. [via]
Researchers grow Biological Hard Drive from Bacteria - [Link]