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Categories: Engineering: Biometric, Physics: Optics
Published A nanocrystal shines on and off indefinitely
(via sciencedaily.com) Original source Optical probes have led to numerous breakthroughs in applications like optical memory, nanopatterning, and bioimaging, but existing options have limited lifespans and will eventually 'photobleach.' New work demonstrates a promising, longer-lasting alternative: ultra-photostable avalanching nanoparticles that can turn on and off indefinitely in response to near-infrared light from simple lasers.
Published Under pressure: Foundations of stellar physics and nuclear fusion investigated
(via sciencedaily.com) Original source Research using the world's most energetic laser has shed light on the properties of highly compressed matter -- essential to understanding the structure of giant planets and stars, and to develop controlled nuclear fusion, a process that could harvest carbon-free energy.
Published Fastest industry standard optical fiber
(via sciencedaily.com) Original source An optical fiber about the thickness of a human hair can now carry the equivalent of more than 10 million fast home internet connections running at full capacity.
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 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 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 Quantum electrodynamics verified with exotic atoms
(via sciencedaily.com) Original source Adapting a detector developed for space X-ray observation, researchers have successfully verify strong-field quantum electrodynamics with exotic atoms.
Published Unlocking the power of photosynthesis for clean energy production
(via sciencedaily.com) Original source Researchers are embarking on a groundbreaking project to mimic the natural process of photosynthesis using bacteria to deliver electrons to a nanocrystal semiconductor photocatalyst. By leveraging the unique properties of microorganisms and nanomaterials, the system has the potential to replace current approaches that derive hydrogen from fossil fuels, revolutionizing the way hydrogen fuel is produced and unlocking a powerful source of renewable energy.