Molecules of hydrogen are difficult to steer with electric fields because of the symmetrical way that charges are distributed within them. But now researchers at ETH Zurich have found a clever technique to get a grip on the molecules. Their findings are reported in Physical Review Letters and highlighted in the September 14 issue of Physics (http://physics.aps.org).
Electric fields can easily manipulate electrically asymmetric molecules like water, but electric forces can't overcome thermal motions for highly symmetric molecules like H2. In the 1980s, researchers in search of a way to manipulate non-polar molecules proposed a trick: excite one of H2's two electrons into a high orbit, disrupting the molecule's symmetry. The far-flung electron feels the pull of the electric field and drags the rest of the molecule along, rendering H2 as manageable as a puppet on a string.
Now Stephen Hogan, Christian Seiler, and Frederic Merkt at ETH Zurich have made this idea reality by overcoming a key problem: an electron in an excited orbit usually reverts to its ground state long before researchers can take advantage of the molecule's maneuverability. They studied several excited orbits in detail, found the longest-lasting ones, and used lasers to select these special states from a group of hydrogen molecules. The newly manageable molecules could be slowed down and trapped for 50 microseconds, plenty of time for the team to study them in detail.
Size isn't the only thing that matters for data storage
Minute magnetic particles, whether bonded to plastic tape or coated onto a hard disk, are the basis of modern data storage. Information is encoded in the magnetic orientation of these nanoparticles, but particles can sometimes switch orientations spontaneously, which can potentially corrupt data. Now researchers from Lawrence Berkeley and Argonne National Laboratories report that this switching unfolds in a more complicated manner than was previously thought. Their work is published in Physical Review Letters and highlighted in the September 14 issue of Physics (http://physics.aps.org).
Scientists have long known that spin flipping becomes more likely as the size of a nanoparticle cluster dwindles. But Stefan Krause and his team discovered that this is not the end of the story. Flipping happens as a kind of chain reaction along a cluster, and the shape of a cluster can help or hinder this propagation. Manipulating the shape of a cluster and even inserting impurities can determine whether a switch is more or less likely to be triggered and propagate, potentially adding a new dimension of control to the design of magnetic devices.
Also in Physics this week:
Guenter Ahlers writes a Trends article in Physics (http://physics.aps.org) on how the unexplored details of convection could hold the key to understanding nature's most impressive phenomena, such as sunspots and patterns in the sun's photosphere.
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The more electronics steer, accelerate and brake cars, the more important it is to protect them against cyber-attacks. That is why 15 partners from industry and academia will work together over the next three years on new approaches to IT security in self-driving cars. The joint project goes by the name Security For Connected, Autonomous Cars (SecForCARs) and has funding of €7.2 million from the German Federal Ministry of Education and Research. Infineon is leading the project.
Vehicles already offer diverse communication interfaces and more and more automated functions, such as distance and lane-keeping assist systems. At the same...
A research team led by physicists at the Technical University of Munich (TUM) has developed molecular nanoswitches that can be toggled between two structurally different states using an applied voltage. They can serve as the basis for a pioneering class of devices that could replace silicon-based components with organic molecules.
The development of new electronic technologies drives the incessant reduction of functional component sizes. In the context of an international collaborative...
At the LASYS 2018, from June 5th to 7th, the Laser Zentrum Hannover e.V. (LZH) will be showcasing processes for the laser material processing of tomorrow in hall 4 at stand 4E75. With blown bomb shells the LZH will present first results of a research project on civil security.
At this year's LASYS, the LZH will exhibit light-based processes such as cutting, welding, ablation and structuring as well as additive manufacturing for...
There are videos on the internet that can make one marvel at technology. For example, a smartphone is casually bent around the arm or a thin-film display is rolled in all directions and with almost every diameter. From the user's point of view, this looks fantastic. From a professional point of view, however, the question arises: Is that already possible?
At Display Week 2018, scientists from the Fraunhofer Institute for Applied Polymer Research IAP will be demonstrating today’s technological possibilities and...
So-called quantum many-body scars allow quantum systems to stay out of equilibrium much longer, explaining experiment | Study published in Nature Physics
Recently, researchers from Harvard and MIT succeeded in trapping a record 53 atoms and individually controlling their quantum state, realizing what is called a...
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