Tue, 24 Jan 2017 05:21:41 ESTThe Ultrafast Optical Processing Group at INRS (Institut national de la recherche scientifique) has redefined the limitations and constraints for ultra-fast pulsed lasers. As reported in Nature Photonics, researchers from the team of Prof. Roberto Morandotti have produced the first pulsed passively mode-locked nanosecond laser, with a record-low and transform-limited spectral width of 105 MHz—more than 100 times lower than any mode-locked laser to date. With a compact architecture, modest power requirements, and the unique ability to resolve the full laser spectrum in the radio frequency (RF) domain, the laser paves the way to full on-chip integration for novel sensing and spectroscopy implementations.
Mon, 23 Jan 2017 17:07:32 ESTWhen a material is made, you typically cannot change whether that material is hard or soft. But a group of University of Michigan researchers have developed a new way to design a "metamaterial" that allows the material to switch between being hard and soft without damaging or altering the material itself.
Mon, 23 Jan 2017 16:49:17 ESTPhysicist Fatima Ebrahimi at the U.S. Department of Energy's (DOE) Princeton Plasma Physics Laboratory (PPPL) has published a paper showing that magnetic reconnection—the process in which magnetic field lines snap together and release energy—can be triggered by motion in nearby magnetic fields. By running computer simulations, Ebrahimi gathered evidence indicating that the wiggling of atomic particles and magnetic fields within electrically charged gas known as plasma can spark the onset of reconnection, a process that, when it occurs on the sun, can spew plasma into space.
Mon, 23 Jan 2017 11:21:26 ESTOne mystery has been whether the jets exist only in the planet's upper atmosphere—much like the Earth's own jet streams—or whether they plunge into Jupiter's gaseous interior. If the latter is true, it could reveal clues about the planet's interior structure and internal dynamics.
Mon, 23 Jan 2017 11:00:10 ESTNature Physics today, Monday, 23 January 2017, published online the research by a team led by physicists from the School of Physics at Wits University. In their paper titled: Characterising quantum channels with non-separable states of classical light the researchers demonstrate the startling result that sometimes Nature cannot tell the difference between particular types of laser beams and quantum entangled photons.
Mon, 23 Jan 2017 08:40:01 EST(Phys.org)—A team of researchers at Washington University in St. Louis has built a camera apparatus capable of capturing moving imagery of an optical Mach cone. In their paper published in the journal Science Advances, the team describes their image capturing system and other possible applications of the technology.
Mon, 23 Jan 2017 07:55:33 ESTCosmologists trying to understand how to unite the two pillars of modern science – quantum physics and gravity – have found a new way to make robust predictions about the effect of quantum fluctuations on primordial density waves, ripples in the fabric of space and time.
Mon, 23 Jan 2017 07:50:01 ESTResearchers at the National Physical Laboratory (NPL) have developed the world's first primary standard for molecular radiotherapy (MRT) to ensure its safe, effective use in the treatment of cancer.
Mon, 23 Jan 2017 06:56:07 ESTDuring his PhD research at Harvard University, AMOLF group leader Bas Overvelde developed a smart method for designing and investigating new metamaterials. For such materials the microstructure determines the function, rather than the molecular composition. The ideal metamaterial changes shape autonomously to achieve the desired functionality. Overvelde and his American colleagues developed a toolkit to design such metamaterials that can assume different shapes in a manner reminiscent of origami. They published their research on 19 January 2017 in Nature.
Mon, 23 Jan 2017 06:52:35 ESTAlthough it sounds hard to believe, everything we see with the naked eye or through microscopes and telescopes accounts for just 4 percent of the known universe. The rest comprises dark energy (69 percent) and dark matter (27 percent). Although there seems to be more dark matter than visible matter in the universe, we still have not been able to directly detect it. The reason is that dark matter does not emit light or absorb electromagnetic waves, so it is really hard to observe. Interestingly, dark matter is needed to explain the motions of galaxies and some of the current theories of galaxy formation and evolution. For example, the galaxy that contains our solar system, the Milky Way, seems to be enveloped by a much larger halo of dark matter; though invisible, its existence is inferred through its effects on the motions of stars and gases.
Mon, 23 Jan 2017 06:30:02 ESTIt might be hard to imagine what link there could be between a huge scientific machine underneath Geneva and a field of tomatoes in Lebanon but both need advanced technology to achieve their best results. Even if they seem light years apart, they face the same technical challenges.
Mon, 23 Jan 2017 05:32:24 ESTPhase transitions surround us—for instance, liquid water changes to ice when frozen and to steam when boiled. Now, researchers at the Carnegie Institution for Science have discovered a new phenomenon of so-called metastability in a liquid phase. A metastable liquid is not quite stable. This state is common in supercooled liquids, which are liquids that cool below the freezing point without turning into a solid or a crystal. Now, scientists report the first experimental evidence of creating a metastable liquid directly by the opposite approach: melting a high-pressure solid crystal of the metal bismuth via a decompression process below its melting point.
Fri, 20 Jan 2017 10:21:39 ESTOptical fibers are the backbone of modern communications, shuttling information from A to B through thin glass filaments as pulses of light. They are used extensively in telecommunications, allowing information to travel at near the speed of light virtually without loss.
Fri, 20 Jan 2017 09:30:01 EST(Phys.org)—Physicists have proposed that violations of energy conservation in the early universe, as predicted by certain modified theories of quantum mechanics and quantum gravity, may explain the cosmological constant problem, which is sometimes referred to as "the worst theoretical prediction in the history of physics."
Fri, 20 Jan 2017 08:52:55 ESTResearchers at the Public University of Navarre (NUP/UPNA) and the Universitat Politècnica de València (UPV) have come up with a new invisibility cloak capable of concealing objects in diffusive atmospheres, not just in direct light.
Fri, 20 Jan 2017 07:42:33 ESTEnterprise networks and data centers continue to increase their demands for connectivity, with ever larger quantities of data expected to be transmitted in the foreseeable future. Over the past 20 years, fiber-optic technology has experienced tremendous success in bringing us a fast, globally-connected internet. Providing greater capacity for information transfer is key to meeting future needs. A recent advancement in fiber core structures promises to help us reach this goal more quickly.
Fri, 20 Jan 2017 02:57:03 ESTWhen matter changes from solids to liquids to vapors, the changes are called phase transitions. Among the most interesting types are more exotic changes—quantum phase transitions—where the strange properties of quantum mechanics can bring about extraordinary changes in curious ways.
Thu, 19 Jan 2017 11:04:38 ESTResearchers at Princeton, Yale, and the University of Zurich have proposed a theory-based approach to characterize a class of metals that possess exotic electronic properties that could help scientists find other, similarly-endowed materials.
Thu, 19 Jan 2017 09:40:01 ESTRecently, fifteen police horses in Gothenburg have contributed to science. They have supported the development of a new method to detect damages in the hooves by using thermoelectric sensors. In the future, hopefully, this technique can be an attractive alternative to other diagnostic tools, for example X-rays.
Thu, 19 Jan 2017 08:18:14 ESTSymmetry is the essential basis of nature, which gives rise to conservation laws. In comparison, the breaking of the symmetry is also indispensable for many phase transitions and nonreciprocal processes. Among various symmetry breaking phenomena, spontaneous symmetry breaking lies at the heart of many fascinating and fundamental properties of nature.
Thu, 19 Jan 2017 06:20:01 ESTWPI-MANA researchers derive topological photonic states purely based on silicon, which can lead to the development of new functions and devices through integration with semiconductor electronics
Thu, 19 Jan 2017 05:45:24 ESTA strong, short light pulse can record data on a magnetic layer of yttrium iron garnet doped with Co-ions. This was discovered by researchers from Radboud University in the Netherlands and Bialystok University in Poland. The novel mechanism outperforms existing alternatives, allowing the fastest read-write magnetic recording accompanied by unprecedentedly low heat load. The research was reported in Nature on January 18 2017.
Thu, 19 Jan 2017 05:00:02 ESTTufts University engineers have invented a chip-sized, high-speed modulator that operates at terahertz (THz) frequencies and at room temperature at low voltages without consuming DC power. The discovery could help fill the "THz gap" that is limiting development of new and more powerful wireless devices that could transmit data at significantly higher speeds than currently possible.
Wed, 18 Jan 2017 13:00:05 ESTAn important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by Professor Alfred Leitenstorfer has now shown how to manipulate the electric vacuum field and thus generate deviations from the ground state of empty space which can only be understood in the context of the quantum theory of light.
Wed, 18 Jan 2017 12:20:42 ESTA University of Iowa physicist is at the forefront of the search for a missing particle that could prove whether the Higgs boson—believed to give mass to all matter—exists.
Wed, 18 Jan 2017 10:43:12 ESTAsegun Henry wants to avert the worst effects of climate change by finding new forms of renewable energy and improving the materials that contribute to energy use.
Wed, 18 Jan 2017 08:34:08 ESTChip scale high precision measurements of physical quantities such as temperature, pressure and refractive index have become common with nanophotonics and nanoplasmonics resonance cavities. As excellent transducers to convert small variations in the local refractive index into measurable spectral shifts, resonance cavities are being used extensively in a variety of disciplines ranging from bio-sensing and pressure gauges to atomic and molecular spectroscopy. Chip-scale microring and microdisk resonators (MRRs) are widely used for these purposes owing to their miniaturized size, relative ease of design and fabrication, high quality factor, and versatility in the optimization of their transfer function.
Wed, 18 Jan 2017 08:30:01 EST(Phys.org)—A team of researchers at Vrije Universiteit Amsterdam has built, for the first time, a molecular fountain. The group has published a paper in the journal Physical Review Letters describing how they created the fountain, how it works and their ideas on how it might be used to more precisely measure physical constants.
Wed, 18 Jan 2017 08:20:02 ESTNeutron detectors and sources play critical roles in national defense, homeland security, nuclear power plant control, radiation medicine, petroleum exploration, materials science, industrial imaging, and a host of other applications. It is essential that these types of devices be tested periodically for accuracy against a radiation standard that emits neutrons at a precisely known and constant rate.
Wed, 18 Jan 2017 06:02:23 ESTOne of the deepest mysteries of physics today is why we seem to live in a world composed only of matter, while the Big Bang should have created equal amounts of matter and antimatter. Around the world, scientists including Stefan Ulmer's team from RIKEN, are designing and carrying out high-precision measurements to try to discover fundamental dissimilarities between matter and antimatter that could lead to the discrepancy.