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Categories: Physics: Optics, Space: General
Published How electron spectroscopy measures exciton 'holes'



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.
Published Molecular manganese complex as superphotooxidant



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.
Published Mysterious gap in size distribution of super-earths explained



Astronomers have uncovered evidence of how the enigmatic gap in the size distribution of exoplanets at around two Earth radii emerges. Their computer simulations demonstrate that the migration of icy, so-called sub-Neptunes into the inner regions of their planetary systems could account for this phenomenon. As they draw closer to the central star, evaporating water ice forms an atmosphere that makes the planets appear larger than in their frozen state. Simultaneously, smaller rocky planets gradually lose a portion of their original gaseous envelope, causing their measured radius to shrink over time.
Published Technique could improve the sensitivity of quantum sensing devices



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.
Published Physicists capture the first sounds of heat 'sloshing' in a superfluid



For the first time, physicists have captured direct images of 'second sound,' the movement of heat sloshing back and forth within a superfluid. The results will expand scientists' understanding of heat flow in superconductors and neutron stars.
Published Spiral-shaped lens provides clear vision at a range of distances and lighting conditions



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.
Published Mimas' surprise: Tiny moon of Saturn holds young ocean beneath icy shell



Saturn's moon Mimas harbors a global ocean beneath its icy shell, discovered through analysis of its orbit by Cassini spacecraft data. This ocean formed just 5-15 million years ago, making Mimas a prime candidate for studying early ocean formation and potential for life. This discovery suggests life-essential conditions might exist on seemingly inactive moons, expanding our search for life beyond Earth.
Published Astrophysicists crack the case of 'disappearing' Sulphur in planetary nebulae



Two astrophysicists have finally solved a 20-year-old astrophysical puzzle concerning the lower-than-expected amounts of the element sulphur found in Planetary Nebulae (PNe) in comparison to expectations and measurements of other elements and other types of astrophysical objects. The expected levels of sulphur have long appeared to be 'missing in action'. However, they have now finally reported for duty after hiding in plain sight, as a result of leveraging highly accurate and reliable data.
Published A long, long time ago in a galaxy not so far away



Employing massive data sets collected through NASA's James Webb Space Telescope, astronomers are unearthing clues to conditions existing in the early universe. The team has catalogued the ages of stars in the Wolf--Lundmark--Melotte (WLM) galaxy, constructing the most detailed picture of it yet, according to the researchers. WLM, a neighbor of the Milky Way, is an active center of star formation that includes ancient stars formed 13 billion years ago.
Published Newly discovered carbon monoxide-runaway gap can help identify habitable exoplanets



A carbon monoxide (CO)-runaway gap identified in the atmospheres of Earth-like planets can help expand the search for habitable planets. This gap, identified through atmospheric modeling, is an indicator of a CO-rich atmosphere on Earth-like planets orbiting Sun-like stars. CO is an important compound for the formation of prebiotic organic compounds, which are building blocks for more complex molecules for the formation of life.
Published Understanding the moon's history with Chang'e-5 sample



China's Chang'e-5, the first lunar sample return mission since the Soviet Union's Luna 24 in 1976, delivered 1.73 kilograms of regolith from the Oceanus Procellarum, a plane named for its vast size. The sample landed with CE-5 in late 2020 and included a new mineral, Changesite-(Y), as well as a perplexing combination of silica minerals. Researchers now compare CE-5's material composition to other lunar and Martian regolith samples and examine potential causes and origins for the lunar sample's unique makeup.
Published Which came first: Black holes or galaxies?



Black holes not only existed at the dawn of time, they birthed new stars and supercharged galaxy formation, a new analysis of James Webb Space Telescope data suggests.
Published Unveiling the generation principles of charged particles 'trion' in 2D semiconductor



Researchers pioneer dynamic manipulation and the generation principles of trion at the nanoscale using tip-enhanced cavity-spectroscopy.
Published Scientists create effective 'spark plug' for direct-drive inertial confinement fusion experiments



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.
Published A sleeker facial recognition technology tested on Michelangelo's David



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.
Published A physical qubit with built-in error correction



Researchers have succeeded in generating a logical qubit from a single light pulse that has the inherent capacity to correct errors.
Published Neptune-like exoplanets can be cloudy or clear



Astronomers have shown new atmospheric detail in a set of 15 exoplanets similar to Neptune. While none could support humanity, a better understanding of their behavior might help us to understand why we don't have a small Neptune, while most solar systems seem to feature a planet of this class.
Published Photonics-based wireless link breaks speed records for data transmission



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.
Published Gas on the run -- ALMA spots the shadow of a molecular outflow from a quasar when the Universe was less than one billion years old



Theoretical predictions have been confirmed with the discovery of an outflow of molecular gas from a quasar when the Universe was less than a billion years old.
Published Short X-ray pulses reveal the source of light-induced ferroelectricity in SrTiO3



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.