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This ultra-thin surface controls light in two completely different ways

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This ultra-thin surface controls light in two completely different ways A new metasurface design lets light of different spins bend, focus, and behave independently—while staying sharp across many colors. The trick combines two geometric phase effects so each spin channel can be tuned without interfering with the other. Researchers demonstrated stable beam steering and dual-focus lenses over wide frequency ranges. The approach could scale from microwaves all the way to visible light. The achromatic lens can focus the incident RCP and LCP light onto two distinct positions without chromatic aberration over a wide bandwidth. Credit: School of Electronic Science and Engineering, Nanjing University Broadband achromatic wavefront control is a key requirement for next-generation optical technologies, including full-color imaging and multi-spectral sensing. Researchers led by Professor Yijun Feng and Professor Ke Chen at Nanjing University have now reported a major advance in this area in Phot...
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Quantum Teleportation Breakthrough Sends 5 States at Once

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Quantum Teleportation Breakthrough Sends 5 States at Once Quantum teleportation is a method for transferring the quantum state of a particle or field from one location to another without physically moving the particle itself. It relies on a phenomenon known as quantum entanglement, in which two systems share strong correlations that cannot be explained by classical physics.  A team in China has demonstrated the simultaneous teleportation of multiple sideband qumodes in a continuous-variable system, overcoming a longstanding technical barrier. Quantum teleportation is one of the key tricks behind entanglement-based quantum communication. It does not move matter from place to place. Instead, it transfers the information that defines a quantum state from one location to another by combining two resources: shared entanglement and an ordinary classical message. In many continuous-variable experiments, that transfer has effectively been a one-at-a-time process. Researchers have usually t...
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Apollo rocks reveal the Moon had brief bursts of super-strong magnetism

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 Apollo rocks reveal the Moon had brief bursts of super-strong magnetism Scientists at the University of Oxford have finally settled a decades-long mystery about the Moon’s magnetic field — and it turns out both sides were right. By reanalyzing Apollo mission rocks, they discovered that the Moon did occasionally generate an incredibly powerful magnetic field, even stronger than Earth’s — but only for fleeting bursts lasting thousands of years or less. Most of the time, the Moon’s magnetic field was weak. The Moon’s magnetic field was mostly weak — but occasionally flared to strengths even greater than Earth’s. Apollo samples exaggerated those powerful moments because astronauts unknowingly collected rocks from rare, titanium-rich hotspots. Credit: Shutterstock Scientists at the University of Oxford's Department of Earth Sciences have settled a decades long argument over the strength of the Moon's magnetic field. For years, researchers have questioned whether the Moon generated ...
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Can solar storms trigger earthquakes? Scientists propose surprising link

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 Can solar storms trigger earthquakes? Scientists propose surprising link Scientists have proposed a surprising connection between solar flares and earthquakes. When solar activity disturbs the ionosphere, it may generate electric fields that penetrate fragile fracture zones in Earth’s crust. If a fault is already critically stressed, this extra electrostatic pressure could help trigger a quake. The idea doesn’t claim direct causation, but it offers a fresh way to think about how space weather and seismic events might interact. A bold new model from Kyoto University suggests that the Sun may play a subtle role in triggering earthquakes.  Scientists at Kyoto University have developed a theoretical model examining whether disturbances in the ionosphere could apply electrostatic forces deep within the Earth's crust. Under certain conditions, these forces might contribute to the start of large earthquakes. The research is not designed to forecast earthquakes. Instead, it outlines ...
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Scientists create ultra-low loss optical device that traps light on a chip

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 Scientists create ultra-low loss optical device that traps light on a chip Scientists have engineered tiny light-trapping racetracks that could supercharge future sensors and quantum technologies. Credit: AI/ScienceDaily.com Researchers at CU Boulder have developed highly efficient optical microresonators that could support a new generation of powerful sensor technologies. A microresonator is a microscopic structure designed to confine light in a small space. As light circulates inside, its intensity increases. When that intensity reaches a sufficient level, scientists can carry out specialized optical processes that enable sensing and other advanced functions."Our work is about using less optical power with these resonators for future uses," said Bright Lu, a fourth year doctoral student in electrical and computer engineering and a lead author on the study. "One day these microresonators can be adapted for a wide range of sensors from navigation to identifying chemical...
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Dark Matter Breakthrough: Physicists Crack “Big Bang Theory” Puzzle

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 Dark Matter Breakthrough: Physicists Crack “Big Bang Theory” Puzzle Physicists have long suspected that elusive particles known as axions could help explain the hidden matter shaping the universe. While the idea even made its way into popular culture, solving the problem proved more difficult than fiction suggested. A new theoretical study suggests fusion reactors could do more than generate energy, they might also produce particles linked to dark matter. Researchers at the University of Cincinnati say they have worked out, at least on paper, how fusion reactors could produce subatomic particles known as axions, a challenge that stumped two of America’s most famous fictional physicists. In the CBS sitcom “The Big Bang Theory,” particle physicists Sheldon Cooper and Leonard Hofstadter, who share an apartment, grapple with the same idea across three episodes in Season 5 but never solve it. UC physics Professor Jure Zupan and his co-authors, all theoretical physicists from the Fermi ...
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Spinning Plasma Solves a Long-Standing Fusion Reactor Mystery

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 Spinning Plasma Solves a Long-Standing Fusion Reactor Mystery For years, researchers have struggled to explain why plasma particles in tokamaks consistently strike the inner divertor more heavily than the outer one, a subtle but crucial imbalance for fusion reactor design. New simulations reveal that the answer lies not only in sideways particle drifts near the exhaust but also in the powerful rotation of the plasma core itself.  A persistent asymmetry in fusion exhaust has challenged researchers for years. New simulations show that plasma core rotation, working together with cross-field drifts, determines where particles land inside a tokamak. Tokamaks are often described as giant magnetic “doughnuts,” built to keep an ultra-hot soup of charged particles suspended long enough for atomic nuclei to fuse and release energy. But even in the best magnetic cages, some of that plasma leaks out. When it does, the particles race along magnetic field lines into a specially engineered ...
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