Commercial devices capable of encrypting information in unbreakable codes exist today, thanks to recent quantum optics advances, especially the generation of photon pairs. Now, an international team is introducing a new method to achieve a different type of photon pair source that fits into the tiny space of a computer chip. The team’s method generates “mixed up” photon pairs from devices that are less than one square millimeter in area.
Drawn relentlessly by their electrical charges, lithium ions in a battery surge from anode to cathode and back again. Yet, no one really understands what goes on at the atomic scale as lithium ion batteries are used and recharged. Using transmission electron microscopy, researchers are now glimpsing what can happen to anodes as lithium ions work their way into them. The “atomic shuffling” these ions perform leads to rapid anode failure.
Ice contains many atoms and molecules trapped inside its structure. A team of Univ. of Chicago and Loyola Univ. researchers has discovered a new mechanism they call "stable energetic embedding" of atoms and molecules within ice. This mechanism explains how some molecules, such as CF4, or "carbon tetrafluoride", interact with and become embedded beneath ice surfaces.
Researchers in the Netherlands can now, for the first time, remotely control a miniature light source at timescales of 200 trillionths of a second. Physicists have developed a way of remotely controlling the nanoscale light sources at an extremely short timescale. These light sources are needed to be able to transmit quantum information.
A Univ. of Texas at Arlington research team says recently identified radiation detection properties of a light-emitting nanostructure built in their lab could open doors for homeland security and medical advances. In a paper to be published in Optics Letters, the team describes a new method to fabricate transparent nanoscintillators by heating nanoparticles composed of lanthanum, yttrium and oxygen until a transparent ceramic is formed.
A novel x-ray technique used at the U.S. Department of Energy’s Advanced Photon Source has revealed surprising dynamics in the nanomechanics of operating batteries and suggests a way to mitigate battery failures by minimizing the generation of elastic energy. The method could open a path to wider use of these batteries in conjunction with renewable energy sources.
Almost all of today’s previously existing cell-sorting methods rely on what is called a single-cell analysis platform. A researcher in Hawaii took a different approach, inventing a bulk method that sorts different cell populations by tuning their solubility. Instead of targeting individual features, the measurement principle sorts cells by differentiating their characteristic surface free energies.
Confined photons have many potential applications, such as efficient miniature lasers, on-chip information storage, or tiny sensors on pharmaceuticals. Making a structure that can capture photons is difficult, but scientists in the Netherlands have recently devised a new type of resonant cavity inside a photonic crystal that imprisons light in all three dimensions.
Electricity and magnetism rule our digital world. Semiconductors process electrical information, while magnetic materials enable long-term data storage. A Univ. of Pittsburgh research team has discovered a way to fuse these two distinct properties in a single material, paving the way for new ultrahigh density storage and computing architectures.
Strong solar flares can bring down communications and power grids on Earth. Physicists in Switzerland have examined the processes that take place when explosions occur on the Sun’s surface and have accurately reconstructed the statistical size distribution and temporal succession of the solar flares with a computer model. This has allowed them to make several new observations about the how these flares occur and behave.
In experiments using graphene, researchers in Switzerland have been able to demonstrate a phenomenon predicted by a Russian physicist more than 50 years ago. The observation of the Lifshitz transition, which describes a change in topology, depended on the creation of a double-layer graphene sample of unprecedented quality.
An international team of physicists has shown that information stored in the nuclear spins of hydrogen isotopes in an organic light-emitting diode (LED) or organic LED can be read out by measuring the electrical current through the device. Unlike previous schemes that only work at ultracold temperatures, this is the first to operate at room temperature, and could be used to create extremely dense and highly energy-efficient memory devices.
Univ. of Minnesota electrical engineering researchers have developed a unique nanoscale device that for the first time demonstrates mechanical transportation of light. The tiny device is just .7 micrometers by 50 micrometers and works almost like a seesaw. On each side of the “seesaw benches,” researchers etched an array of holes, called photonic crystal cavities. These cavities capture photons that streamed from a nearby source.
Inertial confinement fusion creates nanosecond bursts of neutrons, ideal for creating data to plug into supercomputer codes that test the U.S. nuclear stockpile. Down the road, it could be useful as a source of energy. Researchers at Sandia National Laboratories’ Z machine have produced a significant output of fusion neutrons, using a method fully functioning for only little more than a year.
Researchers in Switzerland have succeeded in observing the “forbidden” infrared spectrum of a charged molecule for the first time. These extremely weak spectra offer perspectives for extremely precise measurements of molecular properties and may also contribute to the development of molecular clocks and quantum technology.
Chemical experiments with superheavy elements, which have atomic numbers beyond 104, are extremely challenging because they must be synthesized in a particle accelerator and they decay rapidly. An international team has, for the first time, established a chemical bond between a superheavy element, in this case element 106, seaborgium, and a carbon atom. The experiment opens the door to new investigations of relativity effects.
Chemists at the Univ. of California, Irvine, have scored a scientific first: capturing moving images of a single molecule as it vibrates, or “breathes,” and shifts from one quantum state to another. The groundbreaking achievement, led by Ara Apkarian, professor of chemistry, and Eric Potma, associate professor of chemistry, opens a window into the strange realm of quantum mechanics.
Heat drives classical phase transitions, but much stranger things can happen when the temperature drops. If phase transitions occur at the coldest temperatures imaginable, where quantum mechanics reigns, subtle fluctuations can dramatically transform a material. Scientists have explored this frigid landscape of absolute zero to isolate and probe these quantum phase transitions with unprecedented precision.
In recent years, it has become possible to see directly individual atoms using electron microscopy, especially in graphene. Using electron microscopy and computer simulations, an international team has recently shown how an electron beam can move silicon atoms through the graphene lattice without causing damage.
The central mystery of quantum mechanics is that small chunks of matter sometimes seem to behave like particles, sometimes like waves. For most of the past century, the prevailing explanation of this conundrum has been what’s called the “Copenhagen interpretation”—which holds that, in some sense, a single particle really is a wave, smeared out across the universe, that collapses into a determinate location only when observed.
The central mystery of quantum mechanics is that small chunks of matter sometimes seem to behave like particles, sometimes like waves. The traditional view holds that a single particle really is a wave that collapses only when observed. But John Bush, of the Massachusetts Institute of Technology, believes that another explanation, the pilot-wave theory, deserves a second look.
Scientists at NIST have determined that polonium-209, the longest-lived isotope of this radioactive heavy element, has a half-life about 25% longer than the previously determined value, which had been in use for decades. The new NIST measurements could affect geophysical studies such as the dating of sediment samples from ocean and lake floors.
When moving through a conductive material in an electric field, electrons tend to follow the path of least resistance—which runs in the direction of that field. But now physicists have found an unexpectedly different behavior under very specialized conditions—one that might lead to new types of transistors and electronic circuits that could prove highly energy efficient.
Researchers in Sweden have shown how to use sound to communicate with an artificial atom, in this case an electric circuit that obeys quantum laws. By coupling acoustic waves to the atom, they can demonstrate phenomena from quantum physics with sound taking on the role of light.
A team of Lawrence Berkeley National Laboratory researchers believes it has uncovered the secret behind the unusual optoelectronic properties of single atomic layers of transition metal dichalcogenide (TMDC) materials, the 2-D semiconductors that hold great promise for nanoelectronic and photonic applications.