Helium is a famously unreactive gas but when cooled to just above absolute zero it becomes a superfluid, a strange form of liquid. An Anglo-Austrian team has used this liquid to develop a completely new way of forming charged particles. The team’s key discovery is that helium atoms can acquire an excess negative charge which enables them to become aggressive new chemical reagents.
Certain quantum physical phenomena in matter can only be clearly visualized in the presence of...
An international team of scientists have become the first to successfully reach temperatures...
Scientists at Ames Laboratory have developed deeper understanding of the ideal design for mesoporous nanoparticles used in catalytic reactions, such as hydrocarbon conversion to biofuels. The research will help determine the optimal diameter of channels within the nanoparticles to maximize catalytic output.
Laser physicists in Australia have built a tractor beam that can repel and attract objects, using a hollow laser beam that is bright around the edges and dark in its center. It is the first long-distance optical tractor beam and has moved particles one-fifth of a millimeter in diameter a distance of up to 20 cm, around 100 times further than previous experiments.
Research by an international team of scientists has uncovered a new, unpredicted behavior in a copper oxide material that becomes superconducting at relatively high temperatures. This new phenomenon presents a challenge to scientists seeking to understand its origin and connection with high-temperature superconductivity. Their ultimate goal is to design a superconducting material that works at room temperature.
Joint Quantum Institute scientists have been developing a model for what happens when ultracold atomic spins are trapped in an optical lattice structure with a “double-valley” feature, where the repeating unit resembles the letter “W”. This new theory result opens up a novel path for generating what’s known as the spin Hall effect, an important example of spin-transport.
Like dancers swirling on the dance floor with bystanders looking on, protons and neutrons that have briefly paired up in the nucleus have higher-average momentum, leaving less for non-paired nucleons. Using data from nuclear physics experiments, researchers have now shown for the first time that this phenomenon exists in nuclei heavier than carbon, including aluminum, iron and lead.
Using extremely faint light from galaxies 10.8-billion light-years away, scientists have created one of the most complete, 3-D maps of a slice of the adolescent universe. The map shows a web of hydrogen gas that varies from low to high density at a time when the universe was made of a fraction of the dark matter we see today.
River beds, where flowing water meets silt, sand and gravel, are critical ecological zones. Yet how water flows in a river with a gravel bed is very different from the traditional model of a sandy river bed, according to a new study that compares their fluid dynamics. The findings establish new parameters for river modeling that better represent reality, with implications for field researchers and water resource managers.
Magnetic materials store the vast majority of the 2.7 zettabytes of data that are currently held worldwide. In the interest of efficiency, scientists have begun to investigate whether magnetic materials can also be used to perform calculations. In a recent paper, researchers in the U.K. detail their plan to harness swirling “tornadoes” of magnetization in nanowires to perform logic functions. They plan to soon build prototypes.
In a recent article published in the Review of Scientific Instruments, a research team led by scientists at Lawrence Livermore National Laboratory describe a technique for 3-D image processing of a high-speed photograph of a target, "freezing" its motion and revealing hidden secrets. This technique is particularly applicable in targets that are "shocked."
It’s not as bizarre as it sounds. Earth’s magnetic field has flipped many times throughout the planet’s history. Its dipole magnetic field, like that of a bar magnet, remains about the same intensity for thousands to millions of years, but for incompletely known reasons it occasionally weakens and, presumably over a few thousand years, reverses direction.
Mazhar Ali, a fifth-year graduate student in the laboratory of Bob Cava, the Russell Wellman Moore Professor of Chemistry at Princeton Univ., has spent his academic career discovering new superconductors, materials coveted for their ability to let electrons flow without resistance. While testing his latest candidate, the semimetal tungsten ditelluride (WTe2), he noticed a peculiar result.
Researchers at Oak Ridge National Laboratory have obtained the first direct observations of atomic diffusion inside a bulk material. The research, which could be used to give unprecedented insight into the lifespan and properties of new materials, is published in Physical Review Letters.
In a new experiment, Joint Quantum Institute physicists have performed an experiment using incoherent light, where the light is a jumble of waves, and “stupid” photon detectors that only count to zero. The surprising result from sending this light through a double-slit baffle was a sharp 30-nm-wide interference effect, a new extreme for this type of light detection and a possible new avenue to effective sub-wavelength imaging.
Two research teams working in the same laboratories in Australia have found distinct solutions to a critical challenge that has held back the realization of super powerful quantum computers. The teams created two types of quantum bits, or "qubits", which are the building blocks for quantum computers, that each process quantum data with an accuracy above 99%. They represent parallel pathways for building a quantum computer in silicon.
By focusing on large, star-forming galaxies in the universe, researchers at Johns Hopkins Univ. were able to measure its radiation leaks in an effort to better understand how the universe evolved as the first stars were formed. The team reports in a paper published online in Science that an indicator used for studying star-forming galaxies that leak radiation, is an effective measurement tool for other scientists to use.
When Illinois researchers set out to investigate a method to control how DNA moves through a tiny sequencing device, they didn’t know they were about to witness a display of molecular gymnastics. Fast, accurate and affordable DNA sequencing is the first step toward personalized medicine.
Spectroscopic chemical sensing has great promise, but current technologies lack sensitivity and broad spectral coverage. DARPA’s Spectral Combs from UV to THz (SCOUT) program aims to overcome these limitations. The goal is to develop chip-sized, optical frequency combs that accurately identify even tiny traces of dangerous biological and chemical substances several football fields away, DARPA is now soliciting proposals for a solution.
Researchers at NIST and the Univ. of Michigan have demonstrated a technique based on the quantum properties of atoms that directly links measurements of electric field strength to the International System of Units. The new method could improve the sensitivity, precision and ease of tests and calibrations of antennas, sensors, and biomedical and nano-electronic systems and facilitate the design of novel devices.
Two Americans and a German scientist won the 2014 Nobel Prize in chemistry Wednesday for finding ways to make microscopes more powerful than previously thought possible. Working independently of each other, U.S. researchers Eric Betzig and William Moerner and Stefan Hell of Germany shattered previous limits on the resolution of optical microscopes by using molecules that glow on command to peer inside tiny components of life.
Axons are the shafts of neurons, on the tips of which connections are made with other neurons or cells. In a new study in Texas, researchers were able to use microfluidic stimulations to change the path of an axon at an angle of up to 90 degrees. The publication adds insight to the long accepted idea that chemical cues are primarily responsible for axonal pathfinding during human development and nervous system regeneration.
Scientists at EPFL in Switzerland have designed a first-ever experiment for demonstrating quantum entanglement in the macroscopic realm. Unlike other such proposals, the experiment is relatively easy to set up and run with existing semiconductor devices.
Isamu Akasaki and Hiroshi Amano of Japan and U.S. scientist Shuji Nakamura won the 2014 Nobel Prize in physics for the invention of blue light-emitting diodes, a breakthrough that spurred the development of light-emitting diode (LED) technology. Scientists had struggled for decades to produce the blue diodes that are a crucial component in producing white light from LEDs when the three laureates made their breakthroughs in the early 1990s.
Imagine being able to tune the properties of a solid material just by flashing pulses of light on it. That is one potential payoff of electrons and atoms interacting with ultrashort pulses of light. The technology of ultrafast spectroscopy is a key to understanding this phenomenon and now a new wrinkle to that technology, observations of electron self-energy, has been introduced by Lawrence Berkeley National Laboratory researchers.
At the Vienna Univ. of Technology gold nanoparticles have been coupled to a glass fiber. The particles emit light into the fiber in such a way that it does not travel in both directions, as one would expect. Instead, the light can be directed either to the left or to the right. This became possible by employing the spin-orbit coupling of light, creating a new kind of optical switch that has the potential to revolutionize nanophotonics.
By combining data from two high-energy accelerators, nuclear scientists from Lawrence Berkeley National Laboratory and colleagues have refined the measurement of a remarkable property of exotic matter known as quark-gluon plasma. The findings reveal new aspects of the ultra-hot, “perfect fluid” that give clues to the state of the young universe just microseconds after the big bang.
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