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Description: Physics News and Research. Why is the universe more partial to matter than antimatter? How could fuel cells be more efficient? Read current science articles on physics.

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ScienceDaily: Physics News


Superconducting qubit array points the way to quantum computers
by on Wed, 23 Apr 2014 15:10:33 EDT:
A fully functional quantum computer is one of the holy grails of physics. Physicists have moved one step closer to making a quantum computer a reality by demonstrating a new level of reliability in a five-qubit array. Quantum computing is anything but simple. It relies on aspects of quantum mechanics such as superposition. This notion holds that any physical object, such as an atom or electron -- what quantum computers use to store information -- can exist in all of its theoretical states simultaneously. This could take parallel computing to new heights.
Mapping the road to quantum gravity
by on Wed, 23 Apr 2014 15:09:39 EDT:
The road uniting quantum field theory and general relativity -- the two great theories of modern physics -- has been impassable for 80 years. Could a tool from condensed matter physics finally help map the way?
Atomic switcheroo explains origins of thin-film solar cell mystery
by on Wed, 23 Apr 2014 15:09:37 EDT:
Treating cadmium-telluride (CdTe) solar cell materials with cadmium-chloride improves their efficiency, but researchers have not fully understood why.
Halving hydrogen: First view of nature-inspired catalyst after ripping hydrogen apart provides insights for better fuel cells
by on Wed, 23 Apr 2014 14:28:32 EDT:
A fuel cell catalyst that converts hydrogen into electricity must tear open a hydrogen molecule. Now researchers have captured a view of such a catalyst holding onto the two halves of its hydrogen feast, provides insight into how to make the catalyst work better.
Liquid spacetime: What if spacetime were a kind of fluid?
by on Wed, 23 Apr 2014 09:52:08 EDT:
What if spacetime were a kind of fluid? This is the question tackled by theoretical physicists working on quantum gravity by creating models attempting to reconcile gravity and quantum mechanics. Some of these models predict that spacetime at the Planck scale is no longer continuous – as held by classical physics – but discrete in nature. Just like the solids or fluids we come into contact with every day, which can be seen as made up of atoms and molecules when observed at sufficient resolution. A structure of this kind generally implies, at very high energies, violations of Einstein’s special relativity (a integral part of general relativity).
Quantum simulators developed to study inaccessible physical systems
by on Tue, 22 Apr 2014 11:33:07 EDT:
Quantum simulators recreate the behavior on a microscopic scale of biological and quantum systems and even of particles moving at the speed of light. The exact knowledge of these systems will lead to applications ranging from more efficient photovoltaic cells to more specific drugs. Researchers are working on the design of several of these quantum simulators so they can study the dynamics of complex physical systems.
Superconducting quantum interference devices: Grasp of SQUIDs dynamics facilitates eavesdropping
by on Tue, 22 Apr 2014 10:00:23 EDT:
A superconducting quantum interference device is a highly sensitive magnetometer used to measure extremely subtle magnetic fields. It is made of two thin regions of insulating material that separate two superconductors placed in parallel into a ring of superconducting material. Scientists have focused on finding an analytical approximation to the theoretical equations that govern the dynamics of an array of SQUIDs.
Nanomaterial outsmarts ions: Novel types of electronic components made of graphene
by on Tue, 22 Apr 2014 10:00:17 EDT:
Ions are an essential tool in chip manufacturing, but they can also be used to produce nano-sieves. A large number of electrons must be removed from the atoms for this purpose. Such ions either lose a large amount of energy or almost no energy at all as they pass through a membrane that measures one nanometer in thickness. Researchers report that this discovery is an important step towards developing novel types of electronic components made of graphene.
Higher solar-cell efficiency achieved with zinc-oxide coating
by on Tue, 22 Apr 2014 08:45:15 EDT:
Researchers have achieved 14-percent efficiency in a 9-millimeter-square solar cell made of gallium arsenide. It is the highest efficiency rating for a solar cell that size and made with that material.
Computer-assisted accelerator design
by on Mon, 21 Apr 2014 10:23:25 EDT:
Accelerator physicists are using custom designed software to create a 3-D virtual model of the electron accelerator physicists hope to build inside the tunnel currently housing the Relativistic Heavy Ion Collider at Brookhaven National Laboratory.
Quantum turbulence: New key to unlocking the mysteries of physics?
by on Mon, 21 Apr 2014 09:39:33 EDT:
The recent discovery of the Higgs boson has confirmed theories about the origin of mass and, with it, offered the potential to explain other scientific mysteries. But, scientists are continually studying other, less-understood forces that may also shed light on matters not yet uncovered. Among these is quantum turbulence.
MRI, on a molecular scale: System could one day peer into the atomic structure of individual molecules
by on Fri, 18 Apr 2014 16:14:35 EDT:
A magnetic resonance imaging (MRI) system that can produce nano-scale images, and may one day allow researchers to peer into the atomic structure of individual molecules, has been developed by researchers. For decades, scientists have used techniques like X-ray crystallography and nuclear magnetic resonance imaging (NMR) to gain invaluable insight into the atomic structure of molecules, but such efforts have long been hampered by the fact that they demand large quantities of a specific molecule and often in ordered and crystalized form to be effective -- making it all but impossible to peer into the structure of most molecules.
'Exotic' material is like a switch when super thin
by on Fri, 18 Apr 2014 14:11:19 EDT:
Researchers have shown how to switch a particular transition metal oxide, a lanthanum nickelate, from a metal to an insulator by making the material less than a nanometer thick. Ever-shrinking electronic devices could get down to atomic dimensions with the help of transition metal oxides, a class of materials that seems to have it all: superconductivity, magnetoresistance and other exotic properties. These possibilities have scientists excited to understand everything about these materials, and to find new ways to control their properties at the most fundamental levels.
Impurity size affects performance of emerging superconductive material
by on Fri, 18 Apr 2014 14:11:09 EDT:
Impurities can hurt performance -- or possibly provide benefits -- in a key superconductive material that is expected to find use in a host of applications, including future particle colliders. The size of the impurities determines whether they help or hinder the material's performance, according to new research.
Collider reveals sharp change from 'quark soup' to atoms
by on Fri, 18 Apr 2014 14:07:45 EDT:
Scientists using the atom smasher at the U.S. Department of Energy’s Brookhaven National Laboratory have observed a phase transition different than the smooth transition of the early universe from the hot “soup” of subatomic particles to the atoms, made up of neutrons, protons and electrons that are the building blocks of matter.
Atom probe assisted dating of oldest piece of Earth
by on Thu, 17 Apr 2014 12:41:12 EDT:
It's a scientific axiom: big claims require extra-solid evidence. So when a geoscience professor dated an ancient crystal to 4.4 billion years ago, skeptics questioned the dating. Then, in 2013, researchers put the zircon inside an ultra-precise atom probe and got "data that answered the most serious of the challenges going back to 2001."
Scientists observe quantum superconductor-metal transition and superconducting glass
by on Wed, 16 Apr 2014 17:23:11 EDT:
A new article presents the results of the first experimental study of the graphene-based quantum phase transition of the "superconductor-to-metal" type, i.e. transformation of the system's ground state from superconducting to metallic, upon changing the electron concentration in graphene sheet.
Identifying the complex growth process of strontium titanate thin films
by on Wed, 16 Apr 2014 17:20:31 EDT:
Researchers in Japan have achieved the first successful atomic-level observation of growing strontium titanate thin films.
Information storage for the next generation of plastic computers: Efficient conversion from magnetic storage to light is key
by on Wed, 16 Apr 2014 16:24:50 EDT:
Inexpensive computers, cell phones and other systems that substitute flexible plastic for silicon chips may be one step closer to reality, thanks to new research. Scientists have made a new proposal for overcoming a major obstacle to the development of such plastic devices -- the large amount of energy required to read stored information.
Quantum computing? Progress in the fight against quantum dissipation
by on Wed, 16 Apr 2014 13:34:12 EDT:
Scientists have confirmed a 50-year-old, previously untested theoretical prediction in physics and improved the energy storage time of a quantum switch by several orders of magnitude. High-quality quantum switches are essential for the development of quantum computers and the quantum internet -- innovations that would offer vastly greater information processing power and speed than classical (digital) computers, as well as more secure information transmission.
Searching for dark energy with neutrons: With neutrons, scientists can now look for dark energy in the lab
by on Wed, 16 Apr 2014 13:33:34 EDT:
It does not always take a huge accelerator to do particle physics: First results from a low energy, table top alternative takes validity of Newtonian gravity down by five orders of magnitude and narrows the potential properties of the forces and particles that may exist beyond it by more than one hundred thousand times. Gravity resonance spectroscopy is so sensitive that it can now be used to search for Dark Matter and Dark Energy.
Scientists capture ultrafast snapshots of light-driven superconductivity
by on Wed, 16 Apr 2014 13:32:01 EDT:
A new study pins down a major factor behind the appearance of superconductivity -- the ability to conduct electricity with 100 percent efficiency -- in a promising copper-oxide material. Scientists used carefully timed pairs of laser pulses to trigger superconductivity in the material and immediately take x-ray snapshots of its atomic and electronic structure as superconductivity emerged.
Scientists achieve first direct observations of excitons in motion
by on Wed, 16 Apr 2014 09:08:03 EDT:
A quasiparticle called an exciton -- responsible for the transfer of energy within devices such as solar cells, LEDs, and semiconductor circuits -- has been understood theoretically for decades. But exciton movement within materials has never been directly observed. Now scientists have achieved that feat, imaging excitons' motions directly. This could enable research leading to significant advances in electronics, they say, as well as a better understanding of natural energy-transfer processes, such as photosynthesis.
A small connection with big implications: Wiring up carbon-based electronics
by on Wed, 16 Apr 2014 09:05:36 EDT:
Carbon-based nanostructures such as nanotubes, graphene sheets, and nanoribbons are unique building blocks showing versatile nanomechanical and nanoelectronic properties. These materials which are ordered in the nanoscale, that is, in the dimension of a millionth of millimeter, are promising candidates to envision applications in nanoscale devices, ranging from energy conversion to nano-electronic transistors.
New sensor improves the level of efficiency in detecting ozone
by on Tue, 15 Apr 2014 09:41:41 EDT:
Researchers have developed a more effective ozone sensor than the ones used so far. The new sensor detects this gas faster and in lower amounts. Ozone is present in the atmosphere and it plays a significant role in the protection of living beings because it absorbs the ultraviolet radiation from the sun. However, the exposure to certain concentrations of this gas may cause health problems, such as headache, burning and irritation of the eyes and respiratory system problems; that is why it is relevant to detect its presence effectively.
Beam on target! Cebaf accelerator delivered high-energy electron beams
by on Mon, 14 Apr 2014 14:08:00 EDT:
Late on April 1, the crown jewel of the Department of Energy's Thomas Jefferson National Accelerator Facility sparkled its way into a new era. Following an upgrade of the Continuous Electron Beam Accelerator Facility, the CEBAF accelerator delivered the highest-energy electron beams it has ever produced into a target in an experimental hall, recording the first data of the 12 GeV era.
House windows that double as solar panels? Shiny quantum dots brighten future of solar cells
by on Mon, 14 Apr 2014 12:38:20 EDT:
A house window that doubles as a solar panel could be on the horizon, thanks to recent quantum-dot work. Scientists have demonstrated that superior light-emitting properties of quantum dots can be applied in solar energy by helping more efficiently harvest sunlight.
New 'tunable' semiconductors will allow better detectors, solar cells
by on Mon, 14 Apr 2014 10:12:06 EDT:
Researchers have discovered a way to use existing semiconductors to detect a far wider range of light than is now possible, well into the infrared range. The team hopes to use the technology in detectors, obviously, but also in improved solar cells that could absorb infrared light as well as the sun's visible rays.
Novel technique opens door to better solar cells, superconductors and hard drives
by on Mon, 14 Apr 2014 09:19:58 EDT:
A new invention solves long-standing mystery in the physics of condensed matter and enhances our understanding of interfaces between materials.
Combs of light accelerate communication
by on Mon, 14 Apr 2014 09:19:13 EDT:
Miniaturized optical frequency comb sources allow for transmission of data streams of several terabits per second over hundreds of kilometers. The results may contribute to accelerating data transmission in large computing centers and worldwide communication networks.
New form of matter: Exotic hadron with two quarks, two anti-quarks confirmed
by on Fri, 11 Apr 2014 09:19:47 EDT:
Physicists have confirmed the existence of exotic hadrons -- a type of matter that cannot be classified within the traditional quark model. "We've confirmed the unambiguous observation of a very exotic state -- something that looks like a particle composed of two quarks and two anti-quarks," said one of the scientists. "The discovery certainly doesn't fit the traditional quark model. It may give us a new way of looking at strong-interaction physics."
Search for elusive dark matter: Looking for traces by studying particles with low masses and interaction rates
by on Fri, 11 Apr 2014 09:19:45 EDT:
The ongoing search for invisible dark matter is a subject of great interest to physicists. Although dark matter has never been seen directly, it is thought to be six times more prevalent in the universe than normal matter.
Nanostructures with applications in infrared and terahertz ranges
by on Fri, 11 Apr 2014 09:18:42 EDT:
Scientists have created a compound semiconductor of nearly perfect quality with embedded nanostructures containing ordered lines of atoms that can manipulate light energy in the mid-infrared range. More efficient solar cells, less risky and higher resolution biological imaging, and the ability to transmit massive amounts of data at higher speeds are only a few applications that this unique semiconductor will be able to support.
A modern twist on Young's slits
by on Thu, 10 Apr 2014 16:02:49 EDT:
A landmark experiment on wave interference from the early 1800s is revisited using gold nanoparticles. In the eighteenth century, scientists faced a conundrum: is light a wave or a particle? One of strongest pieces of evidence to support the 'wave view' -- the landmark double-slit experiment -- was reported in 1804 by the scientist Thomas Young. Young passed coherent light through two closely spaced slits and observed a set of interference fringes, a result that occurs with wave phenomena like sound or water. This observation became the basis for the modern wave theory of light.
Researchers bolster development of programmable quantum computers
by on Thu, 10 Apr 2014 13:12:19 EDT:
Scientists have performed a proof-of-concept experiment that will aid the future development of programmable quantum computers. In a new study, the researchers describe an experiment that was performed on a crystal containing trillions, rather than hundreds, of quantum mechanical spins, which replicates some of the features of the current generation of much smaller, specialized computers.
Magnetization can surf on the top of a laser-induced sound wave
by on Thu, 10 Apr 2014 08:34:10 EDT:
An effective coupling between magnetism and light can be mediated by sound. This newly discovered phenomenon could be important for recording data on a magnetic device with the help of light.
Emerging research suggests a new paradigm for 'unconventional superconductors'
by on Wed, 09 Apr 2014 20:45:21 EDT:
Scientists have reported the first experimental observation of the quantum critical point in the extensively studied 'unconventional superconductor' TiSe2, finding that it does not reside as predicted within the superconducting dome of the phase diagram, but rather at a full GPa higher in pressure.
One kind of supersymmetry shown to emerge naturally: Unique phenomenon in condensed matter system
by on Wed, 09 Apr 2014 15:57:48 EDT:
Physicists show that a topological superconductor is conducive to displaying phenomena of emergent supersymmetry. Sought after in the realm of subatomic particles by physicists for several decades, supersymmetry describes a unique relationship between particles.
Scalable, universal quantum computer? Quantum information processed with system comprising optical photon and trapped atom
by on Wed, 09 Apr 2014 15:57:28 EDT:
When it comes to recognizing complex patterns or to decoding encrypted messages, conventional computers reach their limits. A whole new quality in the communication and processing of data is expected from a technology that exploits the special properties of quantum particles such as superposition and entanglement. Scientists are pursuing a variety of different concepts towards the development of such a quantum computer. One professor follows the strategy of combining two rather dissimilar techniques: quantum communication using photons, and information processing using stationary atoms. His team has now for the first time realized a quantum logic gate between a single photon and a single atom.
New 'switch' could power quantum computing: Light lattice traps atoms, builds networks of quantum information transmitters
by on Wed, 09 Apr 2014 13:47:34 EDT:
Using a laser to place individual rubidium atoms near the surface of a lattice of light, scientists have developed a new method for connecting particles -- one that could help in the development of powerful quantum computing systems. The new technique allows researchers to couple a lone atom of rubidium, a metal, with a single photon, or light particle.
Tiny step edges, big step for surface science
by on Wed, 09 Apr 2014 09:39:49 EDT:
New experiments can explain the behavior of electrons at tiny step edges on titanium oxide surfaces. This is important for solar cell technology and novel, more effective catalysts.
Novel ultra-fast electrical circuits use light-generated tunneling currents
by on Wed, 09 Apr 2014 09:36:13 EDT:
Scientists have successfully designed and fabricated electrical circuits that can operate at hundreds of terahertz frequencies, which is tens of thousands times faster than today’s state-of-the-art microprocessors.
Future computers that are normally off
by on Tue, 08 Apr 2014 12:19:20 EDT:
Researchers have broadly envisioned the future of spin-transfer torque magnetoresistive random access memory (STT-MRAM), and they have now described how it will radically alter computer architectures and consumer electronics.
Scalable CVD process for making 2-D molybdenum diselenide
by on Tue, 08 Apr 2014 11:22:14 EDT:
Nanoengineering researchers have unveiled a potentially scalable method for making one-atom-thick layers of molybdenum diselenide -- a material that is similar to graphene but has better properties for making certain electronic devices like switchable transistors and light-emitting diodes.
Rebar technique strengthens case for graphene: Hybrid nanotube-graphene material promises to simplify manufacturing
by on Mon, 07 Apr 2014 13:10:21 EDT:
Carbon nanotubes become reinforcing bars that make two-dimensional graphene much easier to handle in a hybrid material. Chemists set nanotubes into graphene in a way that not only mimics how steel rebar is used in concrete but also preserves and even improves the electrical and mechanical qualities of both. The technique should make large, flexible, conductive and transparent sheets of graphene much easier to manipulate, which should be of interest to electronics manufacturers.
Groundbreaking optical device could enhance optical information processing, computers
by on Sun, 06 Apr 2014 16:24:55 EDT:
At St. Paul's Cathedral in London, a section of the dome called the Whispering Gallery makes a whisper audible from the other side of the dome as a result of the way sound waves travel around the curved surface. Researchers have used the same phenomenon to build an optical device that may lead to new and more powerful computers that run faster and cooler.
Self-assembled silver superlattices create molecular machines with hydrogen-bond 'hinges' and moving 'gears'
by on Sun, 06 Apr 2014 16:22:47 EDT:
A combined computational and experimental study of self-assembled silver-based structures known as superlattices has revealed an unusual and unexpected behavior: arrays of gear-like molecular-scale machines that rotate in unison when pressure is applied to them.
Tracking the transition of early-universe quark soup to matter-as-we-know-it
by on Fri, 04 Apr 2014 13:58:56 EDT:
By smashing together ordinary atomic nuclei at the Relativistic Heavy Ion Collider, scientists recreate the primordial soup of the early universe thousands of times per second. Using sophisticated detectors to track what happens as exotic particles emerge from the collision zone and “freeze out” into more familiar forms of matter, they are turning up interesting details about how the transition takes place.
To bridge LED green gap, think small ... really small: Nanostructures half a DNA strand-wide show promise for efficient LEDs
by on Fri, 04 Apr 2014 09:29:27 EDT:
Nanostructures half the breadth of a DNA strand could improve the efficiency of light emitting diodes according to new simulations. Nanostructure LEDs made from indium nitride could lead to more natural-looking white lighting while avoiding some of the efficiency loss today's LEDs experience at high power.
Light-guiding gels provide new avenues for drug detection, delivery
by on Fri, 04 Apr 2014 08:54:21 EDT:
With the ability to deliver light inside the body in a predictable manner and to host a variety of genetically engineered cells, hydrogels may help address current challenges with applying optogenetic approaches in clinical care. Optogenetics is a relatively new technique that harnesses light to activate or inhibit light-responsive proteins that control specific cell functions.
Quantum computing: Quantum photon properties revealed in another particle -- the plasmon
by on Thu, 03 Apr 2014 21:26:11 EDT:
One approach to make qubits for quantum computing relies on the creation of two single photons that interfere with one another in a device called a waveguide. Results from a recent applied science study support the idea that waveguides coupled with another quantum particle -- the surface plasmon -- could also become an important piece of the quantum computing puzzle.
Quantum cryptography for mobile phones
by on Thu, 03 Apr 2014 13:23:31 EDT:
An ultra-high security scheme that could one day get quantum cryptography using Quantum Key Distribution into mobile devices has been developed and demonstrated. Secure mobile communications underpin our society and through mobile phones, tablets and laptops we have become online consumers. The security of mobile transactions is obscure to most people but is absolutely essential if we are to stay protected from malicious online attacks, fraud and theft.
Fermi data tantalize with new clues to dark matter: Gamma rays from center of Milky Way galaxy
by on Thu, 03 Apr 2014 12:36:28 EDT:
A new study of gamma-ray light from the center of our galaxy makes the strongest case to date that some of this emission may arise from dark matter, an unknown substance making up most of the material universe. Using publicly available data from NASA's Fermi Gamma-ray Space Telescope, independent scientists at the Fermi National Accelerator Laboratory (Fermilab), the Harvard-Smithsonian Center for Astrophysics (CfA), the Massachusetts Institute of Technology (MIT) and the University of Chicago have developed new maps showing that the galactic center produces more high-energy gamma rays than can be explained by known sources and that this excess emission is consistent with some forms of dark matter.
Pocket-size ultrasonic nebulizer employing a novel nozzle improves inhalers
by on Thu, 03 Apr 2014 09:55:11 EDT:
Inhalation is an increasingly important route for non-invasive drug delivery for both systemic and local applications. Control of particle size and output plays a critical role in the efficient and effective delivery of often expensive medications to the lung. Drugs designed to treat pulmonary diseases or for systemic absorption through the alveolar capillary bed require optimum particle sizes for effective delivery.
New insights into quantum dynamics and quantum chaos
by on Wed, 02 Apr 2014 15:36:21 EDT:
A team of researchers has announced analytical prediction and numerical verification of novel quantum rotor states in nanostructured superconductors.
Researchers open path to finding rare, polarized metals
by on Wed, 02 Apr 2014 12:15:58 EDT:
Researchers are turning some of the basic tenets of chemistry and physics upside down to cut a trail toward the discovery of a new set of materials. They're called 'polar metals' and, according to many of the scientific principles that govern the behavior of atoms, they probably shouldn't exist.
Strain can alter materials' properties
by on Wed, 02 Apr 2014 11:16:25 EDT:
In the ongoing search for new materials for fuel cells, batteries, photovoltaics, separation membranes, and electronic devices, one newer approach involves applying and managing stresses within known materials to give them dramatically different properties.
Low-cost, highly efficient OLED lighting: Europium complexes emit red light at record efficiency
by on Wed, 02 Apr 2014 09:54:46 EDT:
Researchers worldwide continue search for better luminescent materials for OLED manufacturing. Two new compounds with europium complexes display in their class record high luminescence efficiencies in red, and their properties enable faster, low cost manufacturing of thin OLED films.
Carbon nanotubes grow in combustion flames
by on Tue, 01 Apr 2014 10:29:10 EDT:
Quantum chemical simulations reveal an unprecedented relationship between the mechanism of carbon nanotube growth and hydrocarbon combustion processes. Results of these simulations illustrate the importance in the role of carbon chemical bonding and molecular transformations in CNT growth.
Electrical transmission at atomic level: New approach to building signal processing components from individual atoms
by on Tue, 01 Apr 2014 10:23:44 EDT:
In a study on the transport of atoms in ultracold gases, a team of physicists has developed a new approach to how signals might be transmitted at the atomic level. This could be especially important for realizing logic structures with strictly defined functions on the basis of individual atoms, which in turn could find application in transistors or diodes.