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Categories: Anthropology: Cultures, Physics: Optics
Published Symmetry breaking by ultrashort light pulses opens new quantum pathways for coherent phonons
(via sciencedaily.com) Original source Researchers have demonstrated a novel concept for exciting and probing coherent phonons in crystals of a transiently broken symmetry. The key of this concept lies in reducing the symmetry of a crystal by appropriate optical excitation, as has been shown with the prototypical crystalline semimetal bismuth (Bi).
Published Source-shifting metastructures composed of only one resin for location camouflaging
(via sciencedaily.com) Original source Acoustic source-shifters make observers mis-perceive the location of sound by reproducing a sound emanating from a location different from the actual location of a sound source. Researchers have now developed a design approach to produce high-performance source-shifters using a common polymer for location camouflage. Utilizing inverse design based on topology optimization, this development could pave the way for advanced augmented reality and holography technology.
Published Evolution driving improvements in racehorse speed
(via sciencedaily.com) Original source A new study has found that genetic improvement is underlying the increasing speed of Britain's thoroughbreds. This contrasts with earlier studies that suggested racehorses were showing no genetic improvement in response to selection by breeders.
Published Biological specimens imaged with X-rays without damage
(via sciencedaily.com) Original source Scientists have managed to image delicate biological structures without damaging them. Their new technique generates high resolution X-ray images of dried biological material that has not been frozen, coated, or otherwise altered beforehand -- all with little to no damage to the sample. This method, which is also used for airport baggage scanning, can generate images of the material at nanometer resolution.
Published Absolute vs. relative efficiency: How efficient are blue LEDs, actually?
(via sciencedaily.com) Original source The absolute internal quantum efficiency (IQE) of indium gallium nitride (InGaN) based blue light-emitting diodes (LEDs) at low temperatures is often assumed to be 100%. However, a new study has found that the assumption of always perfect IQE is wrong: the IQE of an LED can be as low as 27.5%.
Published Emergence of solvated dielectrons observed for the first time
(via sciencedaily.com) Original source Scientists generate low-energy electrons using ultraviolet light.
Published 'A blessing in disguise!' Physics turning bad into good
(via sciencedaily.com) Original source Light is a very delicate and vulnerable property. Light can be absorbed or reflected at the surface of a material depending on the matter's properties or change its form and be converted into thermal energy. Upon reaching a metallic material's surface, light also tends to lose energy to the electrons inside the metal, a broad range of phenomena we call 'optical loss.' Production of ultra-small optical elements that utilize light in various ways is very difficult since the smaller the size of an optical component results in a greater optical loss. However, in recent years, the non-Hermitian theory, which uses optical loss in an entirely different way, has been applied to optics research.
Published Twisting under the stroboscope -- Controlling crystal lattices of hybrid solar cell materials with terahertz light
(via sciencedaily.com) Original source To overcome global energy challenges and fight the looming environmental crisis, researchers around the world investigate new materials for converting sunlight into electricity. Some of the most promising candidates for high-efficiency low-cost solar cell applications are based on lead halide perovskite (LHP) semiconductors. Despite record-breaking solar cell prototypes, the microscopic origin of the surprisingly excellent optoelectronic performance of this material class is still not completely understood. Now, an international team of physicists and chemists has demonstrated laser-driven control of fundamental motions of the LHP atomic lattice.
Published Snapshots of photoinjection
(via sciencedaily.com) Original source Ultrafast laser physicists from the attoworld team have gained new insights into the dynamics of electrons in solids immediately after photoinjection.
Published Keeping time with an atomic nucleus
(via sciencedaily.com) Original source Nuclear clocks could allow scientists to probe the fundamental forces of the universe in the future. Researchers have made a crucial advance in this area as part of an international collaboration.
Published Quantum matter breakthrough: Tuning density waves
(via sciencedaily.com) Original source Scientists have found a new way to create a crystalline structure called a 'density wave' in an atomic gas. The findings can help us better understand the behavior of quantum matter, one of the most complex problems in physics.
Published Breakthrough in computer chip energy efficiency could cut data center electricity use
(via sciencedaily.com) Original source Researchers have made a breakthrough toward reducing the energy consumption of the photonic chips used in data centers and supercomputers.
Published Earliest evidence of wine consumption in the Americas found in Caribbean
(via sciencedaily.com) Original source Scientists have found what they believe to be the earliest known evidence of wine drinking in the Americas, inside ceramic artefacts recovered from a small Caribbean island.
Published Physical chemists develop photochromic active colloids shedding light on the development of new smart active materials
(via sciencedaily.com) Original source In nature, the skin of cephalopods (animals with tentacles attached to the head) exhibits unparalleled camouflage ability. Their skin contains pigment groups that can sense changes in environmental light conditions and adjust their appearance through the action of pigment cells. Although intricate in nature, this colour-changing ability is fundamentally based on a mechanical mechanism in which pigment particles are folded or unfolded under the control of radial muscles. Inspired by this natural process, a research team forms dynamic photochromic nanoclusters by mixing cyan, magenta and yellow microbeads, achieving photochromism on a macro scale.
Published Ancient climate change solves mystery of vanished South African lakes
(via sciencedaily.com) Original source New evidence for the presence of ancient lakes in some of the most arid regions of South Africa suggests that Stone Age humans may have been more widespread across the continent than previously thought.
Published Oldest architectural plans detail mysterious desert mega structures
(via sciencedaily.com) Original source Researchers have identified engravings in Jordan and Saudi Arabia as the oldest known scaled building plans in human history.
Published Humanity's earliest recorded kiss occurred in Mesopotamia 4,500 years ago
(via sciencedaily.com) Original source Written sources from Mesopotamia suggest that kissing in relation to sex was practiced by the peoples of the ancient Middle East 4,500 years ago.
Published Uncovering universal physics in the dynamics of a quantum system
(via sciencedaily.com) Original source New experiments using one-dimensional gases of ultra-cold atoms reveal a universality in how quantum systems composed of many particles change over time following a large influx of energy that throws the system out of equilibrium.
Published Curved spacetime in a quantum simulator
(via sciencedaily.com) Original source The connection between quantum physics and the theory of relativity is extremely hard to study. But now, scientists have set up a model system, which can help: Quantum particles can be tuned in such a way that the results can be translated into information about other systems, which are much harder to observe. This kind of 'quantum simulator' works very well and can lead to new insights about the nature of relativity and quantum physics.
Published South Africa's desert-like interior may have been more inviting to our human ancestors
(via sciencedaily.com) Original source Lining the Cape of South Africa and its southern coast are long chains of caves that nearly 200,000 years ago were surrounded by a lush landscape and plentiful food.