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Feb 23, 2024

Enhanced 3D chemical imaging with phase-modulation

Posted by in categories: biotech/medical, chemistry

Understanding complex biological and biomedical systems is greatly aided by 3D imaging, which provides much more detailed information than traditional two-dimensional methods. However, live cell and tissue imaging remain challenging due to factors like limited imaging speed and significant scattering in turbid environments.

In this context, multimodal microscopy techniques are notable. Specifically, nonlinear techniques like CRS (coherent Raman scattering) use optical vibrational spectroscopy, providing precise chemical imaging in tissues and cells in a label-free way.

Furthermore, stimulated Raman scattering (SRS) microscopy, a CRS method, can accurately capture images of biomolecules due to the linear relationship between stimulated Raman intensity and the concentration of target molecules. It does so with high sensitivity and without interference from unwanted nonresonant backgrounds.

Feb 23, 2024

Experiment paves the way for new set of antimatter studies by laser-cooling positronium

Posted by in categories: particle physics, space

AEgIS is one of several experiments at CERN’s Antimatter Factory producing and studying antihydrogen atoms with the goal of testing with high precision whether antimatter and matter fall to Earth in the same way.

In a paper published today in Physical Review Letters, the AEgIS collaboration reports an experimental feat that will not only help it achieve this goal but also pave the way for a whole new set of antimatter studies, including the prospect to produce a gamma-ray laser that would allow researchers to look inside the atomic nucleus and have applications beyond physics.

Continue reading “Experiment paves the way for new set of antimatter studies by laser-cooling positronium” »

Feb 23, 2024

A new chapter for all-attosecond spectroscopy: Researchers achieve 1 kilohertz repetition rate

Posted by in category: physics

A team of researchers from the Max Born Institute in Berlin has, for the first time, demonstrated attosecond-pump attosecond-probe spectroscopy (APAPS) at a repetition rate of 1 kilohertz. This became possible by the development of a compact, intense attosecond source using an out-of-focus generation geometry. The approach opens new avenues for the investigation of extremely fast electron dynamics in the attosecond regime.

The first generation of pulses (1 attosecond corresponds to 10-18 seconds) at the turn of this century has enabled unprecedented insights into the world of electrons. For their pioneering work, first leading to the demonstration of attosecond pulses in 2001, Anne L’Huillier, Pierre Agostini, and Ferenc Krausz were awarded the Nobel Prize in Physics in 2023.

Current attosecond techniques, however, come with an important drawback: To be able to record a movie in a pump-probe experiment, an attosecond pulse typically has to be combined with a femtosecond pulse (1 femtosecond corresponds to 10-15 seconds) whose optical cycles (a few femtoseconds long) is used as a clock with attosecond resolution. This constitutes a limitation for the investigation of electron dynamics on attosecond timescales.

Feb 23, 2024

Photon upconversion: Steering light with supercritical coupling

Posted by in categories: energy, nanotechnology, physics

National University of Singapore researchers and their collaborators have unveiled a novel concept termed “supercritical coupling” that enables a several-fold increase in photon upconversion efficiency. This discovery not only challenges existing paradigms, but also opens a new direction in the control of light emission.

Photon upconversion, the process of converting low-energy photons into higher-energy ones, is a crucial technique with broad applications, ranging from super-resolution imaging to advanced photonic devices. Despite considerable progress, the quest for efficient upconversion has faced challenges due to inherent limitations in the irradiance of lanthanide-doped nanoparticles and the critical coupling conditions of optical resonances.

The concept of “supercritical coupling” plays a pivotal role in addressing these challenges. This fundamentally new approach, proposed by a research team led by Professor Liu Xiaogang from the Department of Chemistry, NUS and his collaborator, Dr. Gianluigi Zito from the National Research Council of Italy leverages on the physics of “bound states in the continuum” (BICs).

Feb 23, 2024

A Fiery Farewell to ESA’s Pioneering ERS-2 Satellite

Posted by in categories: chemistry, satellites

At approximately 18:17 CET (17:17 UTC) on Wednesday, February 21, 2024, ESA’s ERS-2 satellite completed its atmospheric reentry over the North Pacific Ocean. No damage to property has been reported.

ESA’s second European Remote Sensing satellite, ERS-2, was launched almost 30 years ago, on April 21, 1995. Together with the almost-identical ERS-1, it provided invaluable long-term data on Earth’s land surfaces, ocean temperatures, ozone layer, and polar ice extent that revolutionized our understanding of the Earth system. It was also called upon to monitor and assist the response to natural disasters.

“The ERS satellites have provided a stream of data which has changed our view of the world in which we live,” said ESA’s Director of Earth Observation Programmes, Simonetta Cheli. “They have provided us with new insights on our planet, the chemistry of our atmosphere, the behavior of our oceans, and the effects of mankind’s activity on our environment – creating new opportunities for scientific research and applications.”

Feb 23, 2024

“None of Us Expected This” — Scientists Have Discovered 2D Waveguides

Posted by in categories: nanotechnology, particle physics

The U.S. Naval Research Laboratory (NRL), working together with Kansas State University, has announced the discovery of slab waveguides made from the two-dimensional material hexagonal boron nitride. This milestone has been documented in the journal Advanced Materials.

Two-dimensional (2D) materials are a class of materials that can be reduced to the monolayer limit by mechanically peeling the layers apart. The weak interlayer attractions, or van der Waals attraction, allows the layers to be separated via the so-called “Scotch tape” method. The most famous 2D material, graphene, is a semimetallic material consisting of a single layer of carbon atoms. Recently, other 2D materials including semiconducting transition metal dichalcogenides (TMDs) and insulating hexagonal boron nitride (hBN) have also garnered attention. When reduced near the monolayer limit, 2D materials have unique nanoscale properties that are appealing for creating atomically thin electronic and optical devices.

Feb 23, 2024

Metasurface Magic Unlocks the Future of Holographic Displays

Posted by in categories: augmented reality, holograms

POSTECH’s new metasurface display technology projects angle-dependent holograms, enhancing virtual and augmented reality experiences.

The expression “flawless from every angle” is commonly used to characterize a celebrity’s appearance. This doesn’t simply imply that they appear attractive from a specific viewpoint, but rather that their appeal remains consistent and appealing from various angles and perspectives. Recently, a research team from Pohang University of Science and Technology (POSTECH) has employed metasurface to fabricate angle-dependent holograms with multiple functions, capturing significant interest within the academic community.

Breakthrough in display technology by POSTECH.

Feb 23, 2024

Unlocking Nature’s Secrets: Revolutionary Imaging Unveils Plant Degradation Mysteries

Posted by in categories: chemistry, energy

For years, researchers have dedicated themselves to developing methods that can effectively and economically break down plant materials, enabling their transformation into valuable bioproducts that enhance our daily lives.

Bio-based fuels, detergents, nutritional supplements, and even plastics are the result of this work. And while scientists have found ways to degrade plants to the extent needed to produce a range of products, certain polymers such as lignin, which is a primary ingredient in the cell wall of plants, remain incredibly difficult to affordably break down without adding pollutants back into the environment. These polymers can be left behind as waste products with no further use.

A specialized microbial community composed of fungus, leafcutter ants, and bacteria is known to naturally degrade plants, turning them into nutrients and other components that are absorbed and used by surrounding organisms and systems. But identifying all components and biochemical reactions needed for the process remained a significant challenge—until now.

Feb 23, 2024

The Dual-Laser Revolution: A New Design for Quantum Computers

Posted by in categories: computing, encryption, finance, quantum physics

Creating a quantum computer powerful enough to tackle problems we cannot solve with current computers remains a big challenge for quantum physicists. A well-functioning quantum simulator – a specific type of quantum computer – could lead to new discoveries about how the world works at the smallest scales. Quantum scientist Natalia Chepiga from Delft University of Technology has developed a guide on how to upgrade these machines so that they can simulate even more complex quantum systems. The study is now published in Physical Review Letters.

“Creating useful quantum computers and quantum simulators is one of the most important and debated topics in quantum science today, with the potential to revolutionize society,” says researcher Natalia Chepiga. Quantum simulators are a type of quantum computer, Chepiga explains: “Quantum simulators are meant to address open problems of quantum physics to further push our understanding of nature. Quantum computers will have wide applications in various areas of social life, for example in finances, encryption, and data storage.”

Steering Wheel

Feb 23, 2024

Quantum Breakthrough in High-Temperature Superconductivity

Posted by in categories: particle physics, quantum physics

An international team of scientists has made a new discovery that may help to unlock the microscopic mystery of high-temperature superconductivity and address the world’s energy problems.

In a paper published in the journal Nature, Swinburne University of Technology’s Associate Professor Hui Hu collaborated with researchers at the University of Science and Technology of China (USTC) in a new experimental observation quantifying the pseudogap pairing in a strongly attractive interacting cloud of fermionic lithium atoms.