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Any driver knows it can be hard to remain calm behind the wheel. But perhaps high-tech tools can help. A new study by MIT researchers, announced Thursday, suggests that driver-assistance technologies lower the amount of stress people feel when behind the wheel.

 

The study, conducted over nine months by researchers in the MIT AgeLab in collaboration with the Ford Motor Company and the New England University Transportation Center (NEUTC), monitored drivers as they conducted two generally stress-inducing maneuvers: parallel parking, and backing out into cross-traffic in a parking garage. When using vehicles equipped with driver-assistance systems, however, drivers had lower heart rates, lower reported perceptions of stress, and in some cases operated vehicles more prudently, compared to the times when they operated vehicles entirely manually.

 

The study involved 84 participants, balanced by age and gender, who were divided into two groups, one for each driver-assistance tool. One set of 42 subjects had to execute a dozen parallel-parking maneuvers each on Massachusetts city streets. They drove a Lincoln MKS equipped with Ford’s Active Park Assist tool, which uses cameras and sensors to gauge the size of parking spots, then automatically turns the steering wheel

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The ability of phase-change materials to readily and swiftly switch between different phases has made them valuable for the fabrication of low-power, non-volatile flash memory and data storage devices. Now researchers with the Lawrence Berkeley National Laboratory (Berkeley Lab) and the University of California (UC) Berkeley have discovered an entire new class of phase-change materials that could be utilised in phase-change random access memory technologies and possibly optical data storage as well.  The new phase-change materials are nanocrystalline alloys of a metal and semiconductor called binary eutectic-alloy nanostructures, or BEANs for short.

 

BEAN materials offer the potential for developing phase-change memory (PCM) technologies with better performance than those based on conventional phase-change materials. The researchers suggest that BEANs could be formed into high density arrays of nanowires or quantum dots whose states can be switched from amorphous to crystalline in just nanoseconds.

Conventional PCM materials are made from chalcogenide glass, which can be switched between the crystalline and amorphous states

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An international research group led by scientists at the University of Bristol has developed a new approach to quantum computing that could soon be used to perform complex calculations that cannot be done by today’s computers. Unlike conventional bits or transistors, which can be in one of only two states at any one time (1 or 0), a quantum bit can be in several states at the same time and can therefore hold and process a much larger amount of information at a greater rate. The technique developed in Bristol uses two identical photons moving along a network of circuits in a silicon chip to perform an experiment known as a quantum walk. Quantum walk experiments using one photon have been done before and can even be modelled exactly by classical wave physics. However, this is the first time a quantum walk has been performed with two particles, and the implications are far-reaching. In the short term, the team expect to apply their new results immediately for developing new simulation tools in their own lab. In the longer term, a quantum computer based on a multi-photon quantum walk could be used to simulate processes which themselves are governed by quantum mechanics, such as superconductivity and photosynthesis. The step from one photon to two photons is not trivial because the two particles need to be identical in every way and because of the way these particles interact with each other. There is no direct analogue of this interaction outside of quantum physics. According to one of the researchers, Prof. O’Brien,

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Scientists at the Delft University of Technology (Netherlands) and the Ames Laboratory of the US Department of Energy have managed to fully protect the spin state of a single electron from its environment. Single solid state spins are promising building blocks for new quantum technologies, such as quantum computers, but uncontrolled interactions between spins and their environment have been a major obstacle. By repeatedly flipping the spin of a single electron with very short pulses, the researchers were able to mitigate these effects, effectively decoupling the spin from its environment. They also showed that the technique works with any possible spin state, a stringent requirement for use in a future quantum computer.
The researchers worked with single electrons in diamond, a material that has recently become very popular with quantum scientists. Diamonds have the unique property that quantum mechanical effects can be seen even at room temperature, which is a major advantage for future applications. Previously the researchers were able to measure the spin state of a single electron in diamond and probe its environment. Now, using high-frequency pulses only a few nanoseconds long, the team has achieved control over the state of a single spin with unprecedented accuracy. They have exploited this control to protect the spin from its environment, a groundbreaking result.

The researchers periodically rotated the spin with very high precision so that the environmental effects were fully cancelled by averaging. This caused the spin to be virtually decoupled from its environment. The more often they flipped the spin, the longer its quantum state was preserved. With 130 pulses, the duration of the spin state was 25 times longer than previously measured. In addition, they demonstrated that the protection is effective for any arbitrary spin state.

These results are a true breakthrough for quantum science and engineering, where uncontrolled interactions with the environment have up to now been a major obstacle to new basic research and applications.

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Materials that become superconductive when cooled usually require relative large dimensions, but a research team at Brookhaven National Laboratory, working in collaboration with a team of Israel's Bar-Ilan University, has managed to achieve this with a material formed into nanowires. After fabricating the nanowires, the scientists also discovered that their resistance could be modulated by external magnetic fields. This effect could potentially be used to switch superconductivity on and off magnetically.

The thin-film material, which was cooled to a temperature below approximately 30 degrees Kelvin (-405 degrees Fahrenheit), was made from alternating layers of copper oxide, lanthanum and strontium deposited by molecular beam epitaxy. Electron beam lithography was then used to etch the nanowires, measuring just 25 nanometres in diameter, into a pattern of loops with two different sizes measuring only 150 and 500 nanometres. When an increasing external magnetic field was applied to the wires, the researches found that their resistance was modulated instead of changing linearly as expected. As a result, the researchers hope to engineer a new type of superconducting thin film that allows the superconducting effect to be switched on and off magnetically.

The next objective for the researchers is to discover the mechanism that causes the observed period of the resistance modulation, not only with the aim of developing a new switchable superconducting material but also to increase our understanding of superconductivity. According to the researchers, the observed response to an external magnetic field may help weed out some of the theories that attempt to explain superconductivity, such as potentially discounting the

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Although organic materials have the potential to revolutionize a wide range of high-tech products, such as computer displays and solar cells, they lack the well-ordered chemical structures of organic materials, so this potential is difficult to put into practice. However, a team of researchers led by Dr Dmitrii Perepichka (McGill University, Canada) and Dr Federico Rosei (Institut national de la recherche scientifique, Canada) recently published research that offers a solution to this problem. The team has effectively discovered a way to order the molecules in PEDOT, a conducting polymer with high industrial significance.

Although Dr Perepichka stressed that the research is not directly applicable to current commercial products, he commented:

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A Japanese team says it has extended a high-performance perpendicular tunnel magnetoresistance (TMR) process to nonvolatile logic devices with 40-nanometre dimensions. According to Professor Hideo Ohno of Tohoku University this would allow the fabrication of an 8-Gbit chip with vertical transistors:

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