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Categories: Geoscience: Geology, Physics: Optics
Published Terahertz-to-visible light conversion for future telecommunications



A study demonstrates that graphene-based materials can be used to efficiently convert high-frequency signals into visible light, and that this mechanism is ultrafast and tunable. These outcomes open the path to exciting applications in near-future information and communication technologies.
Published Nanomaterials: 3D printing of glass without sintering



A new process enables printing of nanometer-scale quartz glass structures directly onto semiconductor chips. A hybrid organic-inorganic polymer resin is used as feedstock material for 3D printing of silicon dioxide. Since the process works without sintering, the required temperatures are significantly lower. Simultaneously, increased resolution enables visible-light nanophotonics.
Published Photosynthesis, key to life on Earth, starts with a single photon



A cutting-edge experiment has revealed the quantum dynamics of one of nature's most crucial processes.
Published Earth was created much faster than we thought: This makes the chance of finding other habitable planets in the Universe more likely



Over the past decades, researchers thought Earth was created over a period of more than 100 million years. However, a new study from suggests that the creation of Earth was much more rapid, and that water and other essential ingredients for life were delivered to Earth very early on.
Published Plate tectonics not required for the emergence of life



New finding contradicts previous assumptions about the role of mobile plate tectonics in the development of life on Earth. Moreover, the data suggests that 'when we're looking for exoplanets that harbor life, the planets do not necessarily need to have plate tectonics,' says the lead author of a new paper.
Published Study explains unusual deformation in Earth's largest continental rift



Computer models confirm that the African Superplume is responsible for the unusual deformations, as well as rift-parallel seismic anisotropy observed beneath the East African Rift System.
Published Geologists challenge conventional view of Earth's continental history, stability with new study



The seemingly stable regions of the Earth's continental plates -- the so-called stable cratons -- have suffered repetitive deformation below their crust since their formation in the remote past, according to new research from the University of Illinois Urbana-Champaign. This hypothesis defies decades of conventional plate tectonics theory and begs to answer why most cratons have remained structurally stable while their underbellies have experienced significant change.
Published Researchers describe the melting of gold nanoparticles in gold-bearing fluids in the Earth's crust



Gold is a precious metal that has always fascinated humans. From Priam's Treasure to the legend of El Dorado, gold --regarded as the noblest of metals-- has been a symbol of splendour and wealth in many civilizations. Historically, gold deposits were known to form when metal was transported dissolved by hot aqueous solution flows --hydrothermal fluids-- until it accumulated in some areas in the Earth's upper crust. The recent discovery of gold nanoparticles in such mineral deposits has brought some doubts on the validity of the classical model.
Published New material transforms light, creating new possibilities for sensors



A new class of materials that can absorb low energy light and transform it into higher energy light might lead to more efficient solar panels, more accurate medical imaging and better night vision goggles.
Published Campi Flegrei volcano edges closer to possible eruption



The new study used a model of volcano fracturing to interpret patterns of earthquakes and ground uplift, and concluded that parts of the volcano had been stretched nearly to breaking point.
Published Researchers demonstrate noise-free communication with structured light



Scientists used a new invariant property of vectorial light to encode information. This quantity, which the team call 'vectorness', scales from 0 to 1 and remains unchanged when passing through a noisy channel.
Published Mirror, mirror on the wall... Now we know there are chiral phonons for sure



New findings settle the dispute: phonons can be chiral. This fundamental concept, discovered using circular X-ray light, sees phonons twisting like a corkscrew through quartz.
Published South Africa, India and Australia shared similar volcanic activity 3.5 billion years ago



The Daitari greenstone belt shares a similar geologic make-up when compared to the greenstones exposed in the Barberton and Nondweni areas of South Africa and those from the Pilbara Craton of north-western Australia.
Published Bubble, bubble, more earthquake trouble? Geoscientists study Alaska's Denali fault



Geochemists report findings from collected and analyzed helium and carbon isotopic data from springs along a nearly 250-mile segment of Alaska's Denali Fault. The fault's mantle fluid flow rates, they report, fall in the range observed for the world's other major and active strike-slip faults that form plate boundaries.
Published Researchers demonstrate secure information transfer using spatial correlations in quantum entangled beams of light



Researchers have demonstrated the principle of using spatial correlations in quantum entangled beams of light to encode information and enable its secure transmission.
Published Buckle up! A new class of materials is here



Would you rather run into a brick wall or into a mattress? For most people, the choice is not difficult. A brick wall is stiff and does not absorb shocks or vibrations well; a mattress is soft and is a good shock absorber. Sometimes, in designing materials, both of these properties are needed. Materials should be good at absorbing vibrations, but should be stiff enough to not collapse under pressure. A team of researchers from the UvA Institute of Physics has now found a way to design materials that manage to do both these things.
Published Below the surface: Researchers uncover reasons to rethink how mountains are built



A study suggests that the answers to how and why mountains form are buried deeper than once thought. Clues in the landscape of southern Italy allowed researchers to produce a long-term, continuous record of rock uplift, the longest and most complete record of its kind.
Published Researchers cultivate archaea that break down crude oil in novel ways



The seafloor is home to around one-third of all the microorganisms on the Earth and is inhabited even at a depth of several kilometers. Only when it becomes too hot does the abundance of microorganisms appear to decline. But how, and from what, do microorganisms in the deep seafloor live? How do their metabolic cycles work and how do the individual members of these buried communities interact? Researchers have now been able to demonstrate in laboratory cultures how small, liquid components of crude oil are broken down through a new mechanism by a group of microorganisms called archaea.
Published Flat fullerene fragments attractive to electrons



Researchers have gained new insights into the unique chemical properties of spherical molecules composed entirely of carbon atoms, called fullerenes. They did it by making flat fragments of the molecules, which surprisingly retained and even enhanced some key chemical properties.
Published Petit-spot volcanoes involve the deepest known submarine hydrothermal activity, possibly release CO2 and methane



Underwater volcanism and its hydrothermal activity play an important role in marine biogeochemical cycles, especially the carbon cycle. But the nature of hydrothermal activity at 'petit-spot' volcanoes have not been revealed at all. Now, scientists reveal that petit-spot hydrothermal activity occurs on the deepest seafloor known to date and could release carbon dioxide (CO2) and methane, which may have implications for the global carbon cycle.