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Categories: Offbeat: Paleontology and Archeology, Physics: Optics

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Snail shells are often colorful and strikingly patterned. This is due to pigments that are produced in special cells of the snail and stored in the shell in varying concentrations. Fossil shells, on the other hand, are usually pale and inconspicuous because the pigments are very sensitive and have already decomposed. Residues of ancient color patterns are therefore very rare. This makes a new discovery all the more astonishing: researchers found pigments in twelve-million-year-old fossilized snail shells.

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Semiconductors are ubiquitous in modern technology, working to either enable or prevent the flow of electricity. In order to understand the potential of two-dimensional semiconductors for future computer and photovoltaic technologies, researchers investigated the bond that builds between the electrons and holes contained in these materials. By using a special method to break up the bond between electrons and holes, they were able to gain a microscopic insight into charge transfer processes across a semiconductor interface.

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Highly reducing or oxidizing photocatalysts are a fundamental challenge in photochemistry. Only a few transition metal complexes with Earth-abundant metal ions have so far advanced to excited state oxidants, including chromium, iron, and cobalt. All these photocatalysts require high energy light for excitation and their oxidizing power has not yet been fully exploited. Furthermore, precious and hence expensive metals are the decisive ingredients in most cases. A team of researchers has now developed a new molecular system based on the element manganese. Manganese, as opposed to precious metals, is the third most abundant metal after iron and titanium and hence widely available and very cheap.

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A new technique can control a larger number of microscopic defects in a diamond. These defects can be used as qubits for quantum sensing applications, and being able to control a greater number of qubits would improve the sensitivity of such devices.

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Researchers have developed a spiral-shaped lens that maintains clear focus at different distances in varying light conditions. The new lens works much like progressive lenses used for vision correction but without the distortions typically seen with those lenses. It could help advance contact lens technologies, intraocular implants for cataracts and miniaturized imaging systems.

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Following the arrival of the first farmers in Scandinavia 5,900 years ago, the hunter-gatherer population was wiped out within a few generations, according to a new study. The results, which are contrary to prevailing opinion, are based on DNA analysis of skeletons and teeth found in what is now Denmark.

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The rivers of Australia, which once flowed across its now dry interior, used to host a range of bizarre animals -- including a sleek predatory lobe-finned fish with large fangs and bony scales. The newly described fossil fish discovered in remote fossil fields west of Alice Springs has been named Harajicadectes zhumini by palaeontologists.

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Researchers pioneer dynamic manipulation and the generation principles of trion at the nanoscale using tip-enhanced cavity-spectroscopy.

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Scientists completed several successful attempts to fire 28 kilojoules of laser energy at small capsules filled with deuterium and tritium fuel, causing the capsules to implode and produce a plasma hot enough to initiate fusion reactions between the fuel nuclei. These results demonstrate an effective 'spark plug' for direct-drive methods of inertial confinement fusion.

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Many people are familiar with facial recognition systems that unlock smartphones and game systems or allow access to our bank accounts online. But the current technology can require boxy projectors and lenses. Now, researchers report on a sleeker 3D surface imaging system with flatter, simplified optics. In proof-of-concept demonstrations, the new system recognized the face of Michelangelo's David just as well as an existing smartphone system.

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Researchers have succeeded in generating a logical qubit from a single light pulse that has the inherent capacity to correct errors.

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In the fossil record, trees typically are preserved with only their trunks. They don't usually include any leaves to show what their canopies and overall forms may have looked like. In a new study, researchers describe fossilized trees from New Brunswick, Canada with a surprising and unique three-dimensional crown shape.

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Researchers demonstrated a 300 GHz-band wireless link that was able to transmit data over a single channel at a rate of 240 gigabits per second. The wireless communication system employs signal generators based on lasers that have ultra-low phase noise in the sub-terahertz band. This rate is the highest so far reported at these frequencies and is a substantial step forward in 300 GHz-band communications for 6G networks.

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Researchers have gained new insights into the development of the light-induced ferroelectric state in SrTiO3. They exposed the material to mid-infrared and terahertz frequency laser pulses and found that the fluctuations of its atomic positions are reduced under these conditions. This may explain why the dipolar structure is more ordered than in equilibrium and why the laser pulses induce a ferroelectric state in the material.

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Researchers have successfully developed a new time-resolved atomic force microscopy (AFM) technique, integrating AFM with a unique laser technology. This method enables the measurement of ultrafast photoexcitation phenomena in both conductors and insulators, observed through changes in the forces between the sample and the AFM probe tip after an extremely short time irradiation of laser light. This advancement promises substantial contributions to the creation of new scientific and technological principles and fields.

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Researchers have developed a pioneering method to precisely manipulate ultrafast spin waves in antiferromagnetic materials using tailored light pulses.

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Plasmonics are unique light-matter interactions in the nanoscale regime. Now, a team of researchers has highlighted advances in shadow growth techniques for plasmonic materials, which have the potential to give rise to nanoparticles with diverse shapes and properties. They also introduce a method for large-scale production of nano-rotamers of magnesium with programmable polarization behavior, opening avenues for novel research applications.

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Scientists have developed a new system for imaging nanoparticles. It consists of a high-precision, short-wave infrared imaging technique capable of capturing the photoluminescence lifetimes of rare-earth doped nanoparticles in the micro- to millisecond range.

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Our built environment is aging and failing faster than we can maintain it. Recent building collapses and structural failures of roads and bridges are indicators of a problem that's likely to get worse, according to experts, because it's just not possible to inspect every crack, creak and crumble to parse dangerous signs of failure from normal wear and tear. In hopes of playing catch-up, researchers are trying to give robotic assistants the tools to help inspectors with the job.

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A new way of creating color uses the scattering of light of specific wavelengths around tiny, almost perfectly round silicon crystals. This development enables non-fading structural colors that do not depend on the viewing angle and can be printed. The material has a low environmental and biological impact and can be applied extremely thinly, promising significant weight improvements over conventional paints.