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For decades, scientists have relied on electrodes and dyes to track the electrical activity of living cells. Now, engineers at the University of California San Diego have discovered that quantum materials just a single atom thick can do the job—using only light.

A new study, published in Nature Photonics, shows that these ultra-thin semiconductors, which trap electrons in two dimensions, can be used to sense the biological electrical activity of living cells with high speed and resolution.

Scientists have continually been seeking better ways to track the electrical activity of the body’s most excitable cells, such as neurons, heart muscle fibers and pancreatic cells. These tiny electrical pulses orchestrate everything from thought to movement to metabolism, but capturing them in real time and at large scales has remained a challenge.

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Programmable metasurfaces (PMs), also sometimes referred to as reconfigurable intelligence surfaces, are smart surfaces that reflect wireless signals, but can also dynamically manipulate electromagnetic waves in real-time. These surfaces are highly advantageous for the development of many cutting-edge technologies, including advanced sensing and wireless communication systems.

Researchers at Southeast University, University of Sannio and Université Paris-Saclay-CNRS showed that a specific PM, known as a space-and-time-coding metasurface, could simultaneously support both sensing and wireless communication.

Their paper, published in Nature Communications, introduces two promising schemes for integrated sensing and communication (ISAC) that rely on a space-and-time-coding metasurface they developed.

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Light was long considered to be a wave, exhibiting the phenomenon of interference in which ripples like those in water waves are generated under specific interactions. Light also bends around corners, resulting in fringing effects, which is termed diffraction. The energy of light is associated with its intensity and is proportional to the square of the amplitude of the electric field, but in the photoelectric effect, the energy of emitted electrons is found to be proportional to the frequency of radiation.

This observation was first made by Philipp Lenard, who did initial work on the photoelectric effect. In order to explain this, in 1905, Einstein suggested in Annalen der Physik that light comprises quantized packets of , which came to be called photons. It led to the theory of the dual nature of light, according to which light can behave like a wave or a particle depending on its interactions, paving the way for the birth of quantum mechanics.

Although Einstein’s work on photons found broader acceptance, eventually leading to his Nobel Prize in Physics, Einstein was not fully convinced. He wrote in a 1951 letter, “All the 50 years of conscious brooding have brought me no closer to the answer to the question: What are light quanta?”

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Researchers at NYU Abu Dhabi (NYUAD) have developed an innovative tool that enhances surgeons’ ability to detect and remove cancer cells during cryosurgery, a procedure that uses extreme cold to destroy tumors. This breakthrough technology involves a specialized nanoscale material that illuminates cancer cells under freezing conditions, making them easier to distinguish from healthy tissue and improving surgical precision.

Detailed in the study “Freezing-Activated Covalent Organic Frameworks for Precise Fluorescence Cryo-Imaging of Cancer Tissue” in the Journal of the American Chemical Society, the Trabolsi research group at NYUAD designed a unique nanoscale covalent organic framework (nTG-DFP-COF) that responds to by increasing its fluorescence. This makes it possible to clearly differentiate between cancerous and healthy tissues during surgery.

The material, prepared by Gobinda Das, Ph.D., a researcher in the Trabolsi Research Group at NYUAD, is engineered to be biocompatible and low in toxicity, ensuring it interacts safely within the body. Importantly, it maintains its fluorescent properties even in the presence of ice crystals inside cells, allowing monitoring during cryosurgery.

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Lead-208 is the heaviest known doubly magic nucleus and its structure is therefore of special interest. Despite this magicity, which acts to provide a strong restorative force toward sphericity, it is known to exhibit both strong octupole correlations and some of the strongest quadrupole collectivity observed in doubly magic systems. In this Letter, we employ state-of-the-art experimental equipment to conclusively demonstrate, through four Coulomb-excitation measurements, the presence of a large, negative, spectroscopic quadrupole moment for both the vibrational octupole 3_1^- and quadrupole 2_1^+$ state, indicative of a preference for prolate deformation of the states.

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From computer chips to image sensors in cameras, today’s technology is overwhelmingly based on a semiconductor called silicon. This technology has been shrinking for decades—think of early room-sized computers compared to today’s desktops—but physical limitations will soon prevent further improvement.

That’s why scientists and engineers are preparing for a new generation of technology—one based on quantum mechanics.

The electrons in so-called “” behave differently than those in silicon, enabling more complex behaviors, like magnetism and superconductivity, that are useful for future quantum technologies.

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When a droplet of water falls on a hot pan, it dances across the surface, skimming on a thin layer of steam like a tiny hovercraft; this is known as the Leidenfrost effect. But now, researchers know what happens when a hot droplet falls on a cool surface.

These new findings, published in the journal Newton, demonstrate that hot and burning droplets can bounce off cool surfaces, propelled by a thin layer of air that forms beneath them. This phenomenon could inspire new strategies for slowing the spread of fires and improving engine efficiency.

“We started with a very fundamental question: What will happen when a burning droplet impacts a ?” says senior author Pingan Zhu of City University of Hong Kong, China.

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Quantitative phase imaging (QPI) is a microscopy technique widely used to investigate cells. Even though earlier biomedical applications based on QPI have been developed, both acquisition speed and image quality need to improve to guarantee a widespread reception.

Scientists from the Görlitz-based Center for Advanced Systems Understanding (CASUS) at Helmholtz-Zentrum Dresden-Rossendorf (HZDR) as well as Imperial College London and University College London suggest leveraging an optical phenomenon called chromatic aberration—that usually degrades image quality—to produce suitable images with standard microscopes.

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A team of physicists at the SLAC National Accelerator Laboratory, in Menlo Park, California, generated the highest-current, highest-peak-power electron beams ever produced. The team has published their paper in Physical Review Letters.

For many years, scientists have been finding new uses for high-powered laser light, from splitting atoms to mimicking conditions inside other planets. For this new study, the research team upped the power of electron beams, giving them some of the same capabilities.

The idea behind the newer, more powerful beams was pretty simple, the team acknowledges; it was figuring out how to make it happen that was difficult. The basic idea is to pack as much charge as possible into the shortest amount of time. In their work, they generated 100 kiloamps of current for just one quadrillionth of a second.

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Vanishing atoms can ruin quantum calculations. Scientists have a new plan to locate leaks.

Quantum computers face a major challenge: atoms, which serve as their qubits, can vanish without warning, corrupting calculations. Researchers have developed a groundbreaking method to detect this problem in neutral-atom quantum systems without disrupting their state. This discovery helps overcome a key hurdle in making quantum computing.

Performing computation using quantum-mechanical phenomena such as superposition and entanglement.

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